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Author Verberck, B.; Nikolaev, A.V.; Michel, K.H.
Title Theoretical model for the structural phase transition and the metal-insulator transition in polymerized KC60 Type A1 Journal article
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
Volume 12 Issue 1-2 Pages 243-252
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
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.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000220551600040 Publication Date 2004-03-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1536-383X;1536-4046; ISBN Additional Links UA library record; WoS full record
Impact Factor 1.35 Times cited Open Access
Notes Approved (down) Most recent IF: 1.35; 2004 IF: 1.117
Call Number UA @ lucian @ c:irua:103259 Serial 3607
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Author Nikolaev, A.V.; Michel, K.H.
Title Elusive s-f intrasite interactions and double exchange in solids: ferromagnetic versus nonmagnetic ground state Type A1 Journal article
Year 2009 Publication Journal of experimental and theoretical physics Abbreviated Journal J Exp Theor Phys+
Volume 109 Issue 2 Pages 286-292
Keywords A1 Journal article; Condensed Matter Theory (CMT)
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.
Address
Corporate Author Thesis
Publisher Place of Publication Woodbury, N.Y. Editor
Language Wos 000270506500014 Publication Date 2009-09-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1063-7761;1090-6509; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.196 Times cited 3 Open Access
Notes Approved (down) Most recent IF: 1.196; 2009 IF: 0.871
Call Number UA @ lucian @ c:irua:79163 Serial 1027
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Author Nikolaev, A.V.; Michel, K.H.
Title Many electron- and hole terms of molecular ions C60n\pm Type A1 Journal article
Year 2003 Publication Coupling In Chemistry And Physics Abbreviated Journal Adv Quantum Chem
Volume 44 Issue Pages 305-312
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000188940800019 Publication Date 2004-05-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0065-3276; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.196 Times cited 1 Open Access
Notes Approved (down) Most recent IF: 1.196; 2003 IF: 0.375
Call Number UA @ lucian @ c:irua:104131 Serial 1942
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Author Lamoen, D.; Michel, K.H.
Title Coupling of orientational and translational modes in solid C60 and C70 Type A1 Journal article
Year 1999 Publication Phase transitions Abbreviated Journal Phase Transit
Volume 67 Issue Pages 789
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos 000079806300017 Publication Date 2007-07-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0141-1594;1029-0338; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.06 Times cited 2 Open Access
Notes Approved (down) Most recent IF: 1.06; 1999 IF: 0.622
Call Number UA @ lucian @ c:irua:27830 Serial 537
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Author Bussmann-Holder, A.; Michel, K.H.
Title The isotope effect in hydrogen-bonded systems Type A1 Journal article
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
Volume 12 Issue 29-31 Pages 3406-3408
Keywords A1 Journal article; Condensed Matter Theory (CMT)
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.
Address
Corporate Author Thesis
Publisher Place of Publication Singapore Editor
Language Wos 000079114500104 Publication Date 2003-10-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0217-9792;1793-6578; ISBN Additional Links UA library record; WoS full record
Impact Factor 0.736 Times cited Open Access
Notes Approved (down) Most recent IF: 0.736; 1998 IF: 0.987
Call Number UA @ lucian @ c:irua:102920 Serial 3589
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Author Copley, J.R.D.; Michel, K.H.
Title Neutron and X-ray scattering cross sections of orientationally disordered solid C60 Type A1 Journal article
Year 1993 Publication Journal Of Physics-Condensed Matter Abbreviated Journal J Phys-Condens Mat
Volume 5 Issue Pages 4353-4370
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos A1993LK74100008 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.346 Times cited 34 Open Access
Notes Approved (down) MATERIALS SCIENCE, MULTIDISCIPLINARY 96/271 Q2 #
Call Number UA @ lucian @ c:irua:5778 Serial 2297
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Author Copley, J.R.D.; Michel, K.H.
Title Neutron and X-ray-scattering cross sections of orientationally disordered solid C60 Type A1 Journal article
Year 1993 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 5 Issue 26 Pages 4353-4370
Keywords A1 Journal article; Condensed Matter Theory (CMT)
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.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos A1993LK74100008 Publication Date 2002-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.346 Times cited 34 Open Access
Notes Approved (down) MATERIALS SCIENCE, MULTIDISCIPLINARY 96/271 Q2 #
Call Number UA @ lucian @ c:irua:102972 Serial 2298
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Author Michel, K.H.
Title Sequence of orientational phase transitions in solid C60 Type A1 Journal article
Year 1992 Publication Chemical physics letters Abbreviated Journal Chem Phys Lett
Volume 193 Issue Pages 478-480
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos A1992HZ32900006 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.897 Times cited 14 Open Access
Notes Approved (down) MATERIALS SCIENCE, MULTIDISCIPLINARY 96/271 Q2 #
Call Number UA @ lucian @ c:irua:2971 Serial 2985
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Author Michel, K.H.; Copley, J.R.D.
Title Orientation fluctuations, diffuse scattering and orientational order in solid C60 Type H3 Book chapter
Year 1996 Publication Abbreviated Journal
Volume Issue Pages 381-384
Keywords H3 Book chapter; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher World Scientific Place of Publication Singapore Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved (down) COMPUTER SCIENCE, INTERDISCIPLINARY 11/104 Q1 # PHYSICS, MATHEMATICAL 1/53 Q1 #
Call Number UA @ lucian @ c:irua:16358 Serial 2512
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Author Lamoen, D.; Michel, K.H.
Title Crystal field, orientational order, and lattice contraction in solid C60 Type A1 Journal article
Year 1994 Publication The journal of chemical physics Abbreviated Journal J Chem Phys
Volume 101 Issue Pages 1435-1443
Keywords A1 Journal article; Condensed Matter Theory (CMT)
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.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos A1994NW97900058 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9606; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.952 Times cited 39 Open Access
Notes Approved (down) CHEMISTRY, PHYSICAL 54/144 Q2 # PHYSICS, ATOMIC, MOLECULAR & CHEMICAL 9/35 Q2 #
Call Number UA @ lucian @ c:irua:9361 Serial 554
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Author Michel, K.H.; Lamoen, D.; David, W.I.F.
Title Orientational order and disorder in solid C60 : theory and diffraction experiments Type A1 Journal article
Year 1995 Publication Acta crystallographica: section A: foundations of crystallography Abbreviated Journal Acta Crystallogr A
Volume 51 Issue 3 Pages 365-374
Keywords A1 Journal article; Condensed Matter Theory (CMT)
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.
Address
Corporate Author Thesis
Publisher Place of Publication Copenhagen Editor
Language Wos A1995RB59400018 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0108-7673; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.307 Times cited 14 Open Access
Notes Approved (down) CHEMISTRY, MULTIDISCIPLINARY 65/163 Q2 # CRYSTALLOGRAPHY 10/26 Q2 #
Call Number UA @ lucian @ c:irua:12189 Serial 2518
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Author Michel, K.H.; Copley, J.R.D.; Neumann, D.A.
Title Microscopic theory of orientational disorder and the orientational phase transition in solid C60 Type A1 Journal article
Year 1992 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 68 Issue 19 Pages 2929-2932
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We have developed a microscopic theory which describes the orientational dynamics of C60 molecules in the face-centered-cubic phase of C60 fullerite. The molecular interaction potential and the crystal-field potential are formulated in terms of symmetry-adapted rotator functions. The phase transition to the Pa3BAR structure is driven by an active multipolar mode of T2g symmetry belonging to the l = 10 manifold. The Birman criterion is satisfied. The transition is found to be of first order.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos A1992HT64800019 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.512 Times cited 94 Open Access
Notes Approved (down)
Call Number UA @ lucian @ c:irua:95492 Serial 2032
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Author Lamoen, D.; Michel, K.H.
Title Molecular structure, crystal field and orientational order in solid C60 Type H1 Book chapter
Year 1994 Publication Abbreviated Journal
Volume Issue Pages 183-202
Keywords H1 Book chapter; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication s.l. Editor
Language Wos A1994BE86T00011 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN 0-7923-3109-5 Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved (down)
Call Number UA @ lucian @ c:irua:9355 Serial 2186
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