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Records |
Links |
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Author |
Michel, K.H.; Verberck, B.; Hulman, M.; Kuzmany, H.; Krause, M. |
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Title |
Superposition of quantum and classical rotational motions in Sc2C2@C84 fullerite |
Type |
A1 Journal article |
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Year |
2007 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
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Volume |
126 |
Issue |
6 |
Pages |
064304,1-15 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Corporate Author |
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Place of Publication |
New York, N.Y. |
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Language |
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Wos |
000244250200008 |
Publication Date |
2007-02-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-9606; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.965 |
Times cited |
14 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.965; 2007 IF: 3.044 |
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Call Number |
UA @ lucian @ c:irua:63628 |
Serial |
3381 |
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Permanent link to this record |
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Author |
Lamoen, D.; Michel, K.H. |
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Title |
Crystal field, orientational order, and lattice contraction in solid C60 |
Type |
A1 Journal article |
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Year |
1994 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
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Volume |
101 |
Issue |
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Pages |
1435-1443 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
A model of the intermolecular potential in solid C-60, which is based on Born-Mayer repulsions, van der Waals attractions, and electrostatic multipoles, is presented. The potential is expanded in terms of multipolar rotator functions. The orientation-orientation interaction and the crystal field are calculated. The orientational phase transition to the Pa3 phase is studied with the methods of statistical mechanics. The discontinuity of the order parameter at the transition and the temperature evolution of the order parameter are calculated. The lattice contraction at the phase transition is evaluated. The influence of the lattice contraction on the crystal field and on the orientational order is studied. |
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Place of Publication |
New York, N.Y. |
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Wos |
A1994NW97900058 |
Publication Date |
2002-07-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-9606; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.952 |
Times cited |
39 |
Open Access |
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Notes |
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Approved |
CHEMISTRY, PHYSICAL 54/144 Q2 # PHYSICS, ATOMIC, MOLECULAR & CHEMICAL 9/35 Q2 # |
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Call Number |
UA @ lucian @ c:irua:9361 |
Serial |
554 |
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Permanent link to this record |
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Author |
Michel, K.H. |
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Title |
Molecular structure and orientational ordering in solid C60 |
Type |
A1 Journal article |
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Year |
1992 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
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Volume |
97 |
Issue |
7 |
Pages |
5155-5162 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
A microscopic theory, which describes the orientational dynamics of C60 molecules in the face-centered cubic phase of C60-fullerite, is formulated or the case of a complex molecular structure. Interaction centers which comprise atoms, double bonds, and single bonds as molecular constituents contribute to the intermolecular potential. Orientation dependent physical properties are described in terms of symmetry-adapted rotator functions. It is found that a same set of rotator functions is sufficient even in the case of a complex molecular structure. Phase transition temperatures are discussed for various models of molecular structure. |
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Corporate Author |
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Place of Publication |
New York, N.Y. |
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Language |
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Wos |
A1992JR33800062 |
Publication Date |
2002-07-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-9606; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.952 |
Times cited |
20 |
Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ lucian @ c:irua:2973 |
Serial |
2185 |
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Permanent link to this record |
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Author |
Verberck, B.; Michel, K.H. |
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Title |
Nanotube field of C60 and C70 molecules in carbon nanotubes |
Type |
A1 Journal article |
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Year |
2007 |
Publication |
International journal of quantum chemistry |
Abbreviated Journal |
Int J Quantum Chem |
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Volume |
107 |
Issue |
13 |
Pages |
2294-2319 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000249459800002 |
Publication Date |
2007-02-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0020-7608;1097-461X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.92 |
Times cited |
6 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.92; 2007 IF: 1.368 |
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Call Number |
UA @ lucian @ c:irua:65785 |
Serial |
2282 |
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Permanent link to this record |
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Author |
Copley, J.R.D.; Michel, K.H. |
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Title |
Neutron and X-ray scattering cross sections of orientationally disordered solid C60 |
Type |
A1 Journal article |
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Year |
1993 |
Publication |
Journal Of Physics-Condensed Matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
5 |
Issue |
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Pages |
4353-4370 |
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Keywords |
A1 Journal article; Electron Microscopy for Materials Science (EMAT); |
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Abstract |
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Place of Publication |
London |
Editor |
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Wos |
A1993LK74100008 |
Publication Date |
0000-00-00 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0953-8984 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.346 |
Times cited |
34 |
Open Access |
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Notes |
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Approved |
MATERIALS SCIENCE, MULTIDISCIPLINARY 96/271 Q2 # |
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Call Number |
UA @ lucian @ c:irua:5778 |
Serial |
2297 |
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Permanent link to this record |
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Author |
Copley, J.R.D.; Michel, K.H. |
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Title |
Neutron and X-ray-scattering cross sections of orientationally disordered solid C60 |
Type |
A1 Journal article |
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Year |
1993 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
5 |
Issue |
26 |
Pages |
4353-4370 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Differential cross sections for neutron and x-ray scattering have been derived for the orientationally disordered phase of solid C60. Interaction centres are placed at nuclei and at the centres of interatomic bonds. Bragg and diffuse scattering cross sections, for single crystals and for powders, are formulated using symmetry-adapted rotator functions. Thermal averages are calculated taking account of crystal field effects. Thermally averaged orientational distribution functions have also been calculated. |
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Corporate Author |
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Publisher |
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Place of Publication |
London |
Editor |
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Wos |
A1993LK74100008 |
Publication Date |
2002-08-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.346 |
Times cited |
34 |
Open Access |
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Notes |
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Approved |
MATERIALS SCIENCE, MULTIDISCIPLINARY 96/271 Q2 # |
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Call Number |
UA @ lucian @ c:irua:102972 |
Serial |
2298 |
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Permanent link to this record |
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Author |
Michel, K.H.; Lamoen, D.; David, W.I.F. |
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Title |
Orientational order and disorder in solid C60 : theory and diffraction experiments |
Type |
A1 Journal article |
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Year |
1995 |
Publication |
Acta crystallographica: section A: foundations of crystallography |
Abbreviated Journal |
Acta Crystallogr A |
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Volume |
51 |
Issue |
3 |
Pages |
365-374 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Starting from a microscope model of the intermolecular potential, a unified description is presented of the Bragg scattering law in the orientationally disordered and in the ordered phase of solid C-60. The orientational structure factor is expanded in terms of symmetry-adapted surface harmonics. The expansion coefficients are calculated from theory and compared with experiment Their temperature evolution is studied in the disordered phase at the 260 K transitions and in the ordered phase. In the ordered phase, new results from high-resolution neutron powder diffraction are given. In the disordered phase, space group Fm $($) over bar$$ 3m, the reflections have A(1g) symmetry; in the ordered phase, space group Pa $$($) over bar 3, reflections of T-2g symmetry appear and in addition the A(1g) reflections are renormalized. The orientational density distribution is calculated. The effective crystal-field potential is constructed, its temperature evolution in the ordered phase is studied and related to the occurrence of an orientational glass. |
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Corporate Author |
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Place of Publication |
Copenhagen |
Editor |
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Language |
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Wos |
A1995RB59400018 |
Publication Date |
2002-07-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0108-7673; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.307 |
Times cited |
14 |
Open Access |
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Notes |
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Approved |
CHEMISTRY, MULTIDISCIPLINARY 65/163 Q2 # CRYSTALLOGRAPHY 10/26 Q2 # |
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Call Number |
UA @ lucian @ c:irua:12189 |
Serial |
2518 |
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Permanent link to this record |
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Author |
Bussmann-Holder, A.; Dalal, N.; Michel, K.H. |
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Title |
Polarizability induced cooperative proton ordering, coexistence of order/disorder and displacive dynamics and isotope effects in hydrogen-bonded systems |
Type |
A1 Journal article |
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Year |
2000 |
Publication |
The journal of physics and chemistry of solids
T2 – Williamsburg Workshop on Ferroelectrics 99, JAN 31-FEB 03, 1999, WILLIAMSBURG, VIRGINIA |
Abbreviated Journal |
J Phys Chem Solids |
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Volume |
61 |
Issue |
2 |
Pages |
271-274 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Despite the general belief that hydrogen-bonded ferro- and antiferroelectrics undergo a pure order/disorder transition at the structural instability, new NMR data and a new theoretical concept yield convincing evidence that a pronounced displacive component is present in these systems, which modifies substantially the temperature dependencies of the tunnel and lattice mode frequencies. The experiments and their interpretation are presented. (C) 1999 Elsevier Science Ltd. All rights reserved. |
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Thesis |
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Publisher |
Pergamon-elsevier science ltd |
Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000084147000020 |
Publication Date |
2002-07-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3697; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.059 |
Times cited |
8 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.059; 2000 IF: 1.003 |
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Call Number |
UA @ lucian @ c:irua:103469 |
Serial |
2660 |
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Permanent link to this record |
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Author |
Michel, K.H. |
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Title |
Sequence of orientational phase transitions in solid C60 |
Type |
A1 Journal article |
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Year |
1992 |
Publication |
Chemical physics letters |
Abbreviated Journal |
Chem Phys Lett |
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Volume |
193 |
Issue |
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Pages |
478-480 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
A1992HZ32900006 |
Publication Date |
2002-07-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0009-2614; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.897 |
Times cited |
14 |
Open Access |
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Notes |
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Approved |
MATERIALS SCIENCE, MULTIDISCIPLINARY 96/271 Q2 # |
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Call Number |
UA @ lucian @ c:irua:2971 |
Serial |
2985 |
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Permanent link to this record |
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Author |
Verberck, B.; Michel, K.H. |
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Title |
Anisotropic packing of C-70 molecules in carbon nanotubes |
Type |
A1 Journal article |
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Year |
2007 |
Publication |
Physica status solidi B-basic solid state physics |
Abbreviated Journal |
Phys Status Solidi B |
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Volume |
244 |
Issue |
11 |
Pages |
4279-4282 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000251355800092 |
Publication Date |
2007-10-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-1972;1521-3951; |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
1.674 |
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: 1.674; 2007 IF: 1.071 |
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Call Number |
UA @ lucian @ c:irua:67350 |
Serial |
128 |
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Permanent link to this record |
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Author |
Michel, K.H.; Verberck, B. |
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Title |
Rigid-plane phonons in layered crystals |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
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Volume |
249 |
Issue |
12 |
Pages |
2604-2607 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The determination of the layer number ${\cal N}$ in nanoscale thin layered crystals is a challenging problem of technological relevance. In addition to innovative experimental techniques, a thorough knowledge of the underlying lattice dynamics is required. Starting from phenomenological atomic interaction potentials we have carried out an analytical study of the low-frequency optical phonon dispersions in layered crystals. At the gamma point of the two-dimensional Brillouin zone the optical phonon frequencies correspond to rigid-plane shearing and compression modes. We have investigated graphene multilayers (GML) and hexagonal boron-nitride multilayers (BNML). The frequencies show a characteristic dependence on ${\cal N}$. The results which are represented in the form of fan diagrams are very similar for both materials. Due to charge neutrality within layers Coulomb forces play no role, only van der Waals forces between nearest neighbor layers are relevant. The theoretical results agree with recent low-frequency Raman results on rigid-layer modes [Tan et al., Nature Mater. 11, 294 (2012)] in GML and double-resonant Raman scattering data on rigid-layer compression modes [Herziger et al., Phys. Rev. B 85, 235447 (2012)] in GML. (C) 2012 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000312215300072 |
Publication Date |
2012-11-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-1972; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.674 |
Times cited |
1 |
Open Access |
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Notes |
; This work has been supported by the Flemish Science Foundation (FWO-Vl) and the Bijzonder Onderzoeksfonds, Universiteit Antwerpen (BOF-UA). ; |
Approved |
Most recent IF: 1.674; 2012 IF: 1.489 |
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Call Number |
UA @ lucian @ c:irua:105992 |
Serial |
2907 |
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Permanent link to this record |
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Author |
Michel, K.H.; Verberck, B. |
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Title |
Theoretical phonon dispersions in monolayers and multilayers of hexagonal boron-nitride |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
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Volume |
246 |
Issue |
11/12 |
Pages |
2802-2805 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Starting from an empirical force constant model of valence interactions and calculating by Ewald's method the electrostatic force constants, we derive the dynamical matrix for a monolayer and for multilayer systems of hexagonal boron nitride (h-BN). Solution of the secular problem leads to the corresponding phonon dispersion relations. The interplay between valence forces and Coulomb forces is discussed. A comparison with previous results on graphene and graphene multilayers is made. Our spectra on the h-BN monolayer are rather similar to previous ab initio theory results. Comparison is also made with Raman and infrared experimental results. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000272904100091 |
Publication Date |
2009-11-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-1972; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.674 |
Times cited |
10 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.674; 2009 IF: 1.150 |
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Call Number |
UA @ lucian @ c:irua:80673 |
Serial |
3609 |
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Permanent link to this record |
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Author |
Michel, K.H.; Verberck, B. |
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Title |
Theory of phonon dispersions and piezoelectricity in multilayers of hexagonal boron-nitride |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
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Volume |
248 |
Issue |
11 |
Pages |
2720-2723 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Taking into account covalent, Coulomb and van der Waals interactions, we construct the dynamical matrix and calculate the phonon dispersion relations for multilayer crystals of hexagonal boron-nitride. Coulomb interactions account for a strong overbending of optical phonons. Applying and extending Born's long-wave theory to the case of multilayer crystals, we calculate the piezoelectric stress constant equation image as a function of the number of layers equation image. In agreement with group theory, we find that equation image for equation image even; for an uneven number equation image of layers we obtain equation image, i.e. the piezoelectric constant decreases as equation image. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000297517100069 |
Publication Date |
2011-10-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-1972; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.674 |
Times cited |
13 |
Open Access |
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Notes |
; Discussions with G. Heger, B. Partoens and F. M. Peeters are gratefully acknowledged. This work has been supported by the Flemish Science Foundation (FWO-Vl) and the Bijzonder Onderzoeksfonds, Universiteit Antwerpen (BOF-UA). ; |
Approved |
Most recent IF: 1.674; 2011 IF: 1.316 |
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Call Number |
UA @ lucian @ c:irua:94034 |
Serial |
3618 |
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Permanent link to this record |
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Author |
Michel, K.H.; Verberck, B. |
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Title |
Theory of the elastic constants of graphite and graphene |
Type |
A1 Journal article |
|
Year |
2008 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
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Volume |
245 |
Issue |
10 |
Pages |
2177-2180 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Born's long wave method is used to study the elastic properties of graphite and graphene. Starting from an empirical force constant model derived from full inplane phonon dispersions of graphite [Mohr et al., Phys. Rev. B 76, 035439 (2007)] we calculate the tension coefficients of graphene. Extending the model by interplanar interactions, we calculate the elastic constants of graphite. The agreement of our theoretical values with inelastic x-ray scattering results on elastic constants of graphite [Bosak et al., Phys. Rev. B 75, 153408 (2007)] is very satisfactory. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000260581800066 |
Publication Date |
2008-08-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-1972; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.674 |
Times cited |
47 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.674; 2008 IF: 1.166 |
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Call Number |
UA @ lucian @ c:irua:75660 |
Serial |
3621 |
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Permanent link to this record |
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Author |
Michel, K.H.; Costamagna; Peeters, F.M. |
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Title |
Theory of thermal expansion in 2D crystals |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
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Volume |
252 |
Issue |
252 |
Pages |
2433-2437 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The thermal expansion alpha(T) in layered crystals is of fundamental and technological interest. As suggested by I. M. Lifshitz in 1952, in thin solid films (crystalline membranes) a negative contribution to alpha(T) is due to anharmonic couplings between in-plane stretching modes and out-of-plane bending (flexural modes). Genuine in-plane anharmonicities give a positive contribution to alpha(T). The competition between these two effects can lead to a change of sign (crossover) from a negative value of alpha(T) in a temperature (T) range T <= T-alpha to a positive value of alpha(T) for T > T-alpha in layered crystals. Here, we present an analytical lattice dynamical theory of these phenomena for a two-dimensional (2D) hexagonal crystal. We start from a Hamiltonian that comprises anharmonic terms of third and fourth order in the lattice displacements. The in-plane and out-of-plane contributions to the thermal expansion are studied as functions of T for crystals of different sizes. Besides, renormalization of the flexural mode frequencies plays a crucial role in determining the crossover temperature T-alpha. Numerical examples are given for graphene where the anharmonic couplings are determined from experiments. The theory is applicable to other layer crystals wherever the anharmonic couplings are known. (C) 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000364690400014 |
Publication Date |
2015-08-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-1972 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.674 |
Times cited |
21 |
Open Access |
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Notes |
; We thank B. Verberck, D. Lamoen, and A. Dobry for useful comments. We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. This work is supported by the Euro GRAPHENE project CONGRAN. ; |
Approved |
Most recent IF: 1.674; 2015 IF: 1.489 |
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Call Number |
UA @ lucian @ c:irua:130281 |
Serial |
4264 |
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Permanent link to this record |
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Author |
Michel, K.H.; Neek-Amal, M.; Peeters, F.M. |
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Title |
Static flexural modes and piezoelectricity in 2D and layered crystals |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
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Volume |
253 |
Issue |
253 |
Pages |
2311-2315 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Piezo- and flexoelectricity are manifestations of electromechanical coupling in solids with potential applications in nanoscale materials. Naumov etal. [Phys. Rev. Lett. 102, 217601 (2009)] have shown by first principles calculations that a monolayer BN sheet becomes macroscopically polarized in-plane when in a corrugated state. Here, we investigate the interplay of layer corrugation and in-plane polarization by atomistic lattice dynamics. We treat the coupling between static flexural modes and in-plane atomic ion displacements as an anharmonic effect, similar to the membrane effect that is at the origin of negative thermal expansion in layered crystals. We have derived analytical expressions for the corrugation-induced static in-plane strains and the optical displacements with the resulting polarization response functions. Beyond h-BN, the theory applies to transition metal dichalcogenides and dioxides. Numerical calculations show that the effects are considerably stronger for 2D h-BN than for 2H-MoS2. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000390339000002 |
Publication Date |
2016-10-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-1972 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.674 |
Times cited |
5 |
Open Access |
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Notes |
; The authors acknowledge useful discussions with L. Wirtz, A. Molina-Sanchez, and C. Sevik. This work was supported by the ESF-Eurographene project CONGRAN, and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 1.674 |
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Call Number |
UA @ lucian @ c:irua:140309 |
Serial |
4462 |
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Permanent link to this record |
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Author |
Nikolaev, A.V.; Michel, K.H. |
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Title |
Electronic structure and electric quadrupoles of a polymerized chain in solid AC60 |
Type |
A1 Journal article |
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Year |
2001 |
Publication |
Solid state communications |
Abbreviated Journal |
Solid State Commun |
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Volume |
117 |
Issue |
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Pages |
739-743 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000167538300010 |
Publication Date |
2002-07-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0038-1098; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.554 |
Times cited |
10 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.554; 2001 IF: 1.381 |
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Call Number |
UA @ lucian @ c:irua:36881 |
Serial |
1009 |
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Permanent link to this record |
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Author |
Nikolaev, A.V.; Michel, K.H. |
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Title |
Electric quadrupole interactions and the γ-α phase transition in Ce: the role of conduction electrons |
Type |
A1 Journal article |
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Year |
2000 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
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Volume |
17 |
Issue |
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Pages |
15-32 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000089339900004 |
Publication Date |
2003-05-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1434-6028; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.461 |
Times cited |
8 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.461; 2000 IF: 2.077 |
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Call Number |
UA @ lucian @ c:irua:34338 |
Serial |
888 |
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Permanent link to this record |
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Author |
Michel, K.H.; Verberck, B.; Nikolaev, A.V. |
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Title |
Nanotube field and one-dimensional fluctuations of C60 molecules in carbon nanotubes |
Type |
A1 Journal article |
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Year |
2005 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
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Volume |
48 |
Issue |
1 |
Pages |
113-124 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000233998600016 |
Publication Date |
2005-12-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1434-6028;1434-6036; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.461 |
Times cited |
25 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.461; 2005 IF: 1.720 |
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Call Number |
UA @ lucian @ c:irua:56408 |
Serial |
2279 |
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Permanent link to this record |
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Author |
Nikolaev, A.V.; Michel, K.H. |
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Title |
Quantum charge density fluctuations and the γ-α phase transition in Ce |
Type |
A1 Journal article |
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Year |
1999 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
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Volume |
9 |
Issue |
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Pages |
619-634 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000081615500009 |
Publication Date |
2002-08-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1434-6028; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.461 |
Times cited |
19 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.461; 1999 IF: 1.705 |
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Call Number |
UA @ lucian @ c:irua:28504 |
Serial |
2774 |
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Permanent link to this record |
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Author |
Copley, J.R.D.; Michel, K.H. |
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Title |
Multiple orientational order parameters in solid C60 |
Type |
A1 Journal article |
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Year |
1997 |
Publication |
Physica: B : condensed matter
T2 – International Conference on Neutron Scattering, AUG 17-21, 1997, TORONTO, CANADA |
Abbreviated Journal |
Physica B |
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Volume |
241 |
Issue |
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Pages |
454-455 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The transition Fm (3) over bar m -->Pa (3) over bar in solid C-60 is driven by the condensation of orientational modes belonging to X-5(+) irreducible representations (irreps) of Fm (3) over bar m. Taking into account irreps up to the manifold l = 12, we have studied the primary and secondary orientational order parameters loops). We have numerically solved the coupled molecular field equations for these oops and calculated the temperature dependence of Bragg reflection intensities. (C) 1998 Elsevier Science B.V. All rights reserved. |
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Corporate Author |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000074062600130 |
Publication Date |
2002-07-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0921-4526; |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
1.386 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 1.386; 1997 IF: 0.991 |
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Call Number |
UA @ lucian @ c:irua:104360 |
Serial |
2228 |
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Permanent link to this record |
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Author |
Verberck, B.; Heresanu, V.; Rouziere, S.; Cambedouzou, J.; Launois, P.; Kovats, E.; Pekker, S.; Vliegenthart, G.A.; Michel, K.H.; Gompper, G. |
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Title |
Fullerene-cubane : X-ray scattering experiments and Monte Carlo simulations |
Type |
A1 Journal article |
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Year |
2008 |
Publication |
Fullerenes, nanotubes, and carbon nanostructures
T2 – 8th Biennial International Workshop on Fullerenes and Atomic Clusters, (IWFAC 2007), JUL 02-06, 2007, St Petersburg, RUSSIA |
Abbreviated Journal |
Fuller Nanotub Car N |
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Volume |
16 |
Issue |
5-6 |
Pages |
293-300 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
We report single-crystal X-ray diffuse scattering measurements on C-60.C8H8 fullerene-cubane showing that the C-60 molecules are orientationally disordered at 300 and 150K and get ordered at low temperatures. Monte Carlo simulations provide further insight in the orientational behavior of both C-60 and C8H8 molecules; low-temperature molecular orientations are predicted. |
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Corporate Author |
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Place of Publication |
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Wos |
000259645200003 |
Publication Date |
2008-09-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1536-383X;1536-4046; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.35 |
Times cited |
6 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.35; 2008 IF: 0.680 |
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Call Number |
UA @ lucian @ c:irua:102640 |
Serial |
1295 |
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Permanent link to this record |
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Author |
Verberck, B.; Michel, K.H.; Nikolaev, A.V. |
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Title |
The C60 molecules in (C60)N@SWCNT peapods: crystal field, intermolecular interactions and dynamics |
Type |
A1 Journal article |
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Year |
2006 |
Publication |
Fullerenes, nanotubes, and carbon nanostructures |
Abbreviated Journal |
Fuller Nanotub Car N |
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Volume |
14 |
Issue |
2/3 |
Pages |
171-178 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000238762900006 |
Publication Date |
2006-06-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1536-383X;1536-4046; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.35 |
Times cited |
10 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.35; 2006 IF: 0.462 |
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Call Number |
UA @ lucian @ c:irua:60025 |
Serial |
3518 |
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Permanent link to this record |
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Author |
Verberck, B.; Nikolaev, A.V.; Michel, K.H. |
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Title |
Theoretical model for the structural phase transition and the metal-insulator transition in polymerized KC60 |
Type |
A1 Journal article |
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Year |
2004 |
Publication |
Fullerenes, nanotubes, and carbon nanostructures
T2 – 6th Biennial International Workshop on Fullerenes and Atomic Clusters, JUN 30-JUL 04, 2003, St Petersburg, RUSSIA |
Abbreviated Journal |
Fuller Nanotub Car N |
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Volume |
12 |
Issue |
1-2 |
Pages |
243-252 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
The recently discovered structural phase transition in Polymerized KC60 at about 50K leads to a doubling of the unit cell volume and is accompanied by a metal-insulator transition. Here, we show that the ((a) over right arrow + (c) over right arrow, (b) over right arrow, (a) over right arrow – (c) over right arrow) superstructure results from orientational charge density waves along the polymer chains and correlated displacements of the K+ ions. The presented model can also account for the metal-insulator transition. The effect is specific for the space group Pmnn of KC60 and is absent in both Rb- and CsC60 (space group 12/m), in agreement with the present experimental knowledge of these compounds. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000220551600040 |
Publication Date |
2004-03-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1536-383X;1536-4046; |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
1.35 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 1.35; 2004 IF: 1.117 |
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Call Number |
UA @ lucian @ c:irua:103259 |
Serial |
3607 |
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Permanent link to this record |
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Author |
Nikolaev, A.V.; Michel, K.H. |
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Title |
Elusive s-f intrasite interactions and double exchange in solids: ferromagnetic versus nonmagnetic ground state |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of experimental and theoretical physics |
Abbreviated Journal |
J Exp Theor Phys+ |
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Volume |
109 |
Issue |
2 |
Pages |
286-292 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
From the theory of many-electron states in atoms, we know that there exists a strong Coulomb repulsion, which results in the electronic term structure of atoms and is responsible for Hunds rules. By expanding the Coulomb on-site repulsion into a multipolar series, we derive this interaction and show that it is also present in solids as a correlation effect, which means that the interaction requires a multideterminant version of the Hartree-Fock method. Of particular interest is the case where this interaction couples states of localized ( f) and delocalized ( s) electrons. We show that the interaction is bilinear in the creation/annihilation operators for localized electrons and bilinear in the operators for conduction electrons. To study the coupling, we consider a simple model in the framework of an effective limited configuration interaction method with one localized f-electron and one itinerant s-electron per crystal site. The on-site multipole interaction between the f- and s-electrons is explicitly taken into account. It is shown that depending on the low-lying excitation spectrum imposed by the crystal electric field, the model can lead not only to ferromagnetism but also to a nonmagnetic state. The model is relevant for solids with localized and itinerant electron states. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Woodbury, N.Y. |
Editor |
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Language |
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Wos |
000270506500014 |
Publication Date |
2009-09-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1063-7761;1090-6509; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.196 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.196; 2009 IF: 0.871 |
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Call Number |
UA @ lucian @ c:irua:79163 |
Serial |
1027 |
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Permanent link to this record |
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Author |
Nikolaev, A.V.; Michel, K.H. |
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Title |
Many electron- and hole terms of molecular ions C60n\pm |
Type |
A1 Journal article |
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Year |
2003 |
Publication |
Coupling In Chemistry And Physics |
Abbreviated Journal |
Adv Quantum Chem |
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Volume |
44 |
Issue |
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Pages |
305-312 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000188940800019 |
Publication Date |
2004-05-19 |
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Series Editor |
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Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0065-3276; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.196 |
Times cited |
1 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.196; 2003 IF: 0.375 |
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Call Number |
UA @ lucian @ c:irua:104131 |
Serial |
1942 |
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Permanent link to this record |
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Author |
Lamoen, D.; Michel, K.H. |
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Title |
Coupling of orientational and translational modes in solid C60 and C70 |
Type |
A1 Journal article |
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Year |
1999 |
Publication |
Phase transitions |
Abbreviated Journal |
Phase Transit |
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Volume |
67 |
Issue |
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Pages |
789 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York |
Editor |
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Language |
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Wos |
000079806300017 |
Publication Date |
2007-07-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0141-1594;1029-0338; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.06 |
Times cited |
2 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.06; 1999 IF: 0.622 |
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Call Number |
UA @ lucian @ c:irua:27830 |
Serial |
537 |
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Permanent link to this record |
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Author |
Mattauch, S.; Heger, G.; Michel, K.H. |
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Title |
High resolution neutron and X-ray diffraction studies as a function of temperature and electric field of the ferroelectric phase transition of RDP |
Type |
A1 Journal article |
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Year |
2004 |
Publication |
Crystal research and technology |
Abbreviated Journal |
Cryst Res Technol |
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Volume |
39 |
Issue |
12 |
Pages |
1027-1054 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Neutron and high resolution X-ray diffraction investigations on perfect single crystals of RbH2PO4 (RDP), a hydrogen bonded ferroelectric of KDP type are reported. The results of crystal structure analysis from diffraction data, below and above the paraelectric – ferroelectric phase transition, support a disorder – order character Of [PO4H2](-)-groups. The tetragonal symmetry of the paraelectric phase with the double well potential of the hydrogen atoms obtained by diffraction, results simply from a time-space average of orthorhombic symmetry. According to the group – subgroup relation between the tetragonal space group 142d and the orthorhombic Fdd2 a short range order of ferroelectric clusters in the tetragonal phase is observed. With decreasing temperature the ferroelectric clusters increase and the long range interaction between their local polarisation vectors leads to the formation of lamellar ferroelectric domains with alternating polarisation directions at T-C = 147 K. From the high resolution X-ray data it is concluded that below T-C the ferroelastic strain in the (a,b)-plane leads to micro-angle grain boundaries at the domain walls. The tilt angle is enhanced by an applied electric field parallel to the ferroelectric axis. The resulting dislocations at the domain walls persist in the paraelectric phase leading to a memory effect for the arrangement of twin lamellae. With increased electric field the phase transition temperature T-C is decreased. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000225681100001 |
Publication Date |
2004-11-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0232-1300;1521-4079; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1 |
Times cited |
12 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1; 2004 IF: 0.770 |
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Call Number |
UA @ lucian @ c:irua:94785 |
Serial |
1459 |
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Permanent link to this record |
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Author |
Bussmann-Holder, A.; Michel, K.H. |
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Title |
The isotope effect in hydrogen-bonded systems |
Type |
A1 Journal article |
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Year |
1998 |
Publication |
International journal of modern physics: B: condensed matter physics, statistical physics, applied physics
T2 – 1st International Conference on New Theories, Discoveries, and, Applications of Superconductors and Related Materials (New3SC-1), FEB 19-24, 19 |
Abbreviated Journal |
Int J Mod Phys B |
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Volume |
12 |
Issue |
29-31 |
Pages |
3406-3408 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The giant isotope effect on the ferro- and antiferroelectric transition temperature upon deuteration of hydrogen-bonded systems is well known experimentally since various decades. Yet, theoretically only recently a microscopic understanding of this effect has been achieved which, specifically, took into account the geometry of the O ... H ... O bond. The implications of this modeling are multiple as numerous hydrogen-bonded organic systems show the same effects as ferro- and antiferroelectrics, i.e., cooperative proton tunneling at a well-defined temperature. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Singapore |
Editor |
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Language |
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Wos |
000079114500104 |
Publication Date |
2003-10-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0217-9792;1793-6578; |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
0.736 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 0.736; 1998 IF: 0.987 |
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Call Number |
UA @ lucian @ c:irua:102920 |
Serial |
3589 |
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Permanent link to this record |
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Author |
Nikolaev, A.V.; Michel, K.H. |
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Title |
Ab initio approach to superexchange interactions in alkali doped fullerides AC60 |
Type |
P1 Proceeding |
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Year |
2004 |
Publication |
AIP conference proceedings
T2 – 18th International Winterschool/Euroconference on Electronic Properties, of Novel Materials, MAR 06-JUN 13, 2004, Kirchberg, AUSTRIA |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
393-396 |
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Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
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Abstract |
The superexchange interactions between the fullerenes arise as a result of the electron transfer from the C-60 molecule to the alkali atom and back. We present a scheme, which is a configuration interaction approach based on the valence bond (Heitler-London) method. The effect of superexchange is described together with chemical bonding by constructing and solving a secular equation, rather than by using a perturbation treatment. We have considered 180degrees and 90degrees superexchange for the C-60 Cs-C-60 pathways. The calculations account for unusual electronic properties of polymer orthorhombic and quenched cubic phases of CsC60: two lines in nuclear magnetic resonance experiments, the development of a spin-singlet ground state and a decrease of magnetic susceptibility as T-->0. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York |
Editor |
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Language |
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Wos |
000224699400085 |
Publication Date |
2004-11-11 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
723 |
Series Issue |
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Edition |
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ISSN |
0-7354-0204-3 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:103752 |
Serial |
27 |
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Permanent link to this record |