Records |
Author |
Michel, K.H.; Nikolaev, A.V.; Verberck, B. |
Title |
Theory of crystal structures of polymerized C60-fullerite and fullerides AC60, A=K, Rb, Cs |
Type |
H1 Book chapter |
Year |
2001 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
H1 Book chapter; Condensed Matter Theory (CMT) |
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 |
s.l. |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
462-465 |
Series Issue |
|
Edition |
|
ISSN |
|
ISBN |
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Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:36883 |
Serial |
3614 |
Permanent link to this record |
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Author |
Tsvyashchenko, A.V.; Nikolaev, A.V.; Velichkov, A.I.; Salamatin, A.V.; Fomicheva, L.N.; Ryasny, G.K.; Sorokin, A.A.; Kochetov, O.I.; Budzynski, M.; Michel, K.H. |
Title |
Lowering of the spatial symmetry at the gamma ->alpha phase transition in cerium |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
82 |
Issue |
9 |
Pages |
1-4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using time-differential perturbed angular correlation spectroscopy we have measured the electric field gradient (EFG) at 111Cd probe nuclei in solid Ce in a pressure range up to 8 GPa. Covering various allotropic phases of Ce, we find that the value of the EFG in the cubic α phase is almost four times larger than in the cubic γ phase and close to values in the noncubic phases α′ and α″. These results together with the differences in time modulation of the spectra are interpreted as evidence for quadrupolar electronic charge-density ordering and symmetry lowering at the γ→α transition while the lattice remains face-centered cubic |
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 |
000282004400001 |
Publication Date |
2010-09-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
11 |
Open Access |
|
Notes |
; This work is supported by the Program of the Presidium of the Russian Academy of Sciences “Physics of Strongly Compressed Matter.” We are grateful to S. M. Stishov, B. Verberck, A. N. Grum-Grzhimailo, V. B. Brudanin and G. Heger for support of this work and discussion of the results. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:85464 |
Serial |
1854 |
Permanent link to this record |
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Author |
Nikolaev, A.V.; Michel, K.H. |
Title |
Microscopic theory of quadrupolar oredring in TmTe |
Type |
A1 Journal article |
Year |
2001 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
63 |
Issue |
|
Pages |
1-10 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000167402100025 |
Publication Date |
2002-07-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
7 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2001 IF: NA |
Call Number |
UA @ lucian @ c:irua:36882 |
Serial |
2033 |
Permanent link to this record |
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|
|
Author |
Nikolaev, A.V.; Michel, K.H. |
Title |
Electric quadrupole interactions and the γ-α phase transition in Ce: the role of conduction electrons |
Type |
A1 Journal article |
Year |
2000 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
Volume |
17 |
Issue |
|
Pages |
15-32 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
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 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1434-6028; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.461 |
Times cited |
8 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.461; 2000 IF: 2.077 |
Call Number |
UA @ lucian @ c:irua:34338 |
Serial |
888 |
Permanent link to this record |
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|
Author |
Michel, K.H.; Verberck, B.; Nikolaev, A.V. |
Title |
Nanotube field and one-dimensional fluctuations of C60 molecules in carbon nanotubes |
Type |
A1 Journal article |
Year |
2005 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
Volume |
48 |
Issue |
1 |
Pages |
113-124 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
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 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1434-6028;1434-6036; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.461 |
Times cited |
25 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.461; 2005 IF: 1.720 |
Call Number |
UA @ lucian @ c:irua:56408 |
Serial |
2279 |
Permanent link to this record |
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|
|
Author |
Verberck, B.; Michel, K.H.; Nikolaev, A.V. |
Title |
The C60 molecules in (C60)N@SWCNT peapods: crystal field, intermolecular interactions and dynamics |
Type |
A1 Journal article |
Year |
2006 |
Publication |
Fullerenes, nanotubes, and carbon nanostructures |
Abbreviated Journal |
Fuller Nanotub Car N |
Volume |
14 |
Issue |
2/3 |
Pages |
171-178 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
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Language |
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Wos |
000238762900006 |
Publication Date |
2006-06-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1536-383X;1536-4046; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.35 |
Times cited |
10 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.35; 2006 IF: 0.462 |
Call Number |
UA @ lucian @ c:irua:60025 |
Serial |
3518 |
Permanent link to this record |
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|
|
Author |
Nikolaev, A.V.; Michel, K.H.; Copley, J.R.D. |
Title |
Orientational disorder and order in C60-fullerite and in MC60-alkali metal fullerides |
Type |
H3 Book chapter |
Year |
1999 |
Publication |
|
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
183-214 |
Keywords |
H3 Book chapter; Condensed Matter Theory (CMT) |
Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Plenum Press |
Place of Publication |
New York |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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 |
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ISBN |
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Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:28505 |
Serial |
2515 |
Permanent link to this record |
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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 |
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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 |
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 |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
1.35 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.35; 2004 IF: 1.117 |
Call Number |
UA @ lucian @ c:irua:103259 |
Serial |
3607 |
Permanent link to this record |
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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 |
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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 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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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 |
Most recent IF: 1.196; 2009 IF: 0.871 |
Call Number |
UA @ lucian @ c:irua:79163 |
Serial |
1027 |
Permanent link to this record |
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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 |
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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 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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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 |
Most recent IF: 1.196; 2003 IF: 0.375 |
Call Number |
UA @ lucian @ c:irua:104131 |
Serial |
1942 |
Permanent link to this record |
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Author |
Verberck, B.; Popov, V.N.; Nikolaev, A.V.; Lamoen, D. |
Title |
Valence electronic charge density of distorted C60-monomers in polymerized KC60 and RbC60 |
Type |
A1 Journal article |
Year |
2004 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
Volume |
121 |
Issue |
|
Pages |
321 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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 |
000222112100035 |
Publication Date |
2004-06-16 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-9606; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.965 |
Times cited |
7 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.965; 2004 IF: 3.105 |
Call Number |
UA @ lucian @ c:irua:47380 |
Serial |
3830 |
Permanent link to this record |
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|
|
Author |
Verberck, B.; Nikolaev, A.V.; Michel, K.H. |
Title |
Orientational charge density waves and the metal-insulator transition in polymerized KC60 |
Type |
A1 Journal article |
Year |
2004 |
Publication |
AIP conference proceedings |
Abbreviated Journal |
|
Volume |
723 |
Issue |
|
Pages |
339-342 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Polymerized KC60 undergoes a structural phase transition accompanied by a metal-insulator transition around 50 K. To explain the structural aspect, a mechanism involving small orientational deviations of the valence electron density on every C-60 monomer orientational charge density waves (OCDWs) – has already been proposed earlier. In the present work, we address the metal-insulator transition using the OCDW concept. We are inspired by the analogy between a polymer chain exhibiting an OCDW and a linear atomic chain undergoing a static lattice deformation doubling the unit cell: such a deformation implies a band gap at the zone boundary, yielding an insulating state (Peierls instability). Within our view, a similar mechanism occurs in polymerized KC60; the OCDW plays the role of the lattice deformation. We present tight-binding band structure calculations and conclude that the metal-insulator transition can indeed be explained using OCDWs, but that the threedimensionality of the crystal plays an unexpected key role. |
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 |
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Publication Date |
0000-00-00 |
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 |
|
ISSN |
0094-243x |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:94831 |
Serial |
2513 |
Permanent link to this record |
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|
|
Author |
Nikolaev, A.V.; Michel, K.H. |
Title |
Ab initio approach to superexchange interactions in alkali doped fullerides AC60 |
Type |
P1 Proceeding |
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 |
|
Volume |
|
Issue |
|
Pages |
393-396 |
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
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. |
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 |
|
Wos |
000224699400085 |
Publication Date |
2004-11-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
723 |
Series Issue |
|
Edition |
|
ISSN |
0-7354-0204-3 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:103752 |
Serial |
27 |
Permanent link to this record |
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|
|
Author |
Nikolaev, A.V.; Michel, K.H. |
Title |
Molecular terms and optical transitions of C60n+/- molecular ions |
Type |
P1 Proceeding |
Year |
2002 |
Publication |
AIP conference proceedings
T2 – 16th International Winterschool on Electronic Properties of Novel, Materials, MAR 02-09, 2002, KIRCHBERG, AUSTRIA |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
417-420 |
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
We have studied the molecular energy terms of the hole configurations (h(u)(+))(m), m=2,3,4,5 of C-60(m+) cations and the electronic configurations (t(1u))(n) n=2,3,4, as well as (t(1u))(n-1)t(1g) of the C-60(n-) anions. The lowest terms (within an energy span of 0.03 eV) for C-60(2+) are three triplets T-3(1g), (3)G(g), T-3(2g) and for C-60(3+) are three quartets T-4(1u), (4)G(u), T-4(2u), which favor Jahn-Teller distortions. For the ground state of C-60(2-) we find a triplet T-3(1g) in agreement with Hund's rules. Our method takes into account intramolecular direct and exchange multipolar Coulomb interactions. |
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 |
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Publication Date |
0000-00-00 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
|
Series Volume |
633 |
Series Issue |
|
Edition |
|
ISSN |
0-7354-0088-1 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:103905 |
Serial |
2187 |
Permanent link to this record |
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|
|
Author |
Nikolaev, A.V.; Prassides, K.; Michel, K.H. |
Title |
Phase transitions in AC60 (A=Rb, Cs) fullerides |
Type |
A3 Journal article |
Year |
1997 |
Publication |
Recent advances in the chemistry and physics of fullerenes and related materials |
Abbreviated Journal |
|
Volume |
5 |
Issue |
|
Pages |
450-460 |
Keywords |
A3 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
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 |
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Publication Date |
0000-00-00 |
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 |
|
Edition |
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ISSN |
|
ISBN |
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Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:21182 |
Serial |
2596 |
Permanent link to this record |
|
|
|
Author |
Nikolaev, A.V.; Michel, K.H. |
Title |
Quantum charge density fluctuations and the γ-α phase transition in Ce |
Type |
A1 Journal article |
Year |
1999 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
Volume |
9 |
Issue |
|
Pages |
619-634 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Berlin |
Editor |
|
Language |
|
Wos |
000081615500009 |
Publication Date |
2002-08-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1434-6028; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.461 |
Times cited |
19 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.461; 1999 IF: 1.705 |
Call Number |
UA @ lucian @ c:irua:28504 |
Serial |
2774 |
Permanent link to this record |
|
|
|
Author |
Nikolaev, A.V.; Michel, K.H. |
Title |
Electronic structure and electric quadrupoles of a polymerized chain in solid AC60 |
Type |
A1 Journal article |
Year |
2001 |
Publication |
Solid state communications |
Abbreviated Journal |
Solid State Commun |
Volume |
117 |
Issue |
|
Pages |
739-743 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000167538300010 |
Publication Date |
2002-07-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0038-1098; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.554 |
Times cited |
10 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.554; 2001 IF: 1.381 |
Call Number |
UA @ lucian @ c:irua:36881 |
Serial |
1009 |
Permanent link to this record |
|
|
|
Author |
Nikolaev, A.V.; Verberck, B.; Ionova, G.V. |
Title |
Molecular interaction energies and optimal configuration of a cubane dimer |
Type |
A1 Journal article |
Year |
2010 |
Publication |
International journal of quantum chemistry |
Abbreviated Journal |
Int J Quantum Chem |
Volume |
110 |
Issue |
5 |
Pages |
1063-1069 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We have studied the dependence of the binding energy of a cubane dimer on the mutual orientation of and the distance between the composing monomers employing the second-order Møller-Plesset perturbation scheme (MP2) with the cc-pVDZ molecular basis set. We have found that the MP2 contribution from the molecular correlations is responsible for the bound state of the cubane dimer, whereas the Hartree-Fock contribution remains anti-bonding at all intermolecular distances. Starting with two molecules in the standard orientation and centers of mass at (0,0,0) and (0,0,d), respectively, the maximal binding energy is found at d = 5.125 Å and one of the monomers rotated by 45° about the z-axis. This configuration implies that the hydrogen atoms belonging to different monomers tend to repel each other. The results are in agreement with experimental data on the optimal packing of cubane molecules in the solid state. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000274720000011 |
Publication Date |
2009-04-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0020-7608;1097-461X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.92 |
Times cited |
1 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 2.92; 2010 IF: 1.302 |
Call Number |
UA @ lucian @ c:irua:81944 |
Serial |
2179 |
Permanent link to this record |
|
|
|
Author |
Michel, K.H.; Nikolaev, A.V. |
Title |
Theory of distinct crystal structures of polymerized fullerides AC60, A=K, Rb, Cs: the specific role of alkalis |
Type |
A1 Journal article |
Year |
2000 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
Volume |
85 |
Issue |
|
Pages |
3197-3200 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000089807800033 |
Publication Date |
2002-07-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.462 |
Times cited |
16 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 8.462; 2000 IF: 6.462 |
Call Number |
UA @ lucian @ c:irua:34339 |
Serial |
3615 |
Permanent link to this record |
|
|
|
Author |
Nikolaev, A.V.; Prassides, K.; Michel, K.H. |
Title |
Charge transfer and polymer phases in AC60 (A=K, Rb, Cs) fullerides |
Type |
A1 Journal article |
Year |
1998 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
Volume |
108 |
Issue |
|
Pages |
4912-4923 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000072588400025 |
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 |
2.965 |
Times cited |
14 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.965; 1998 IF: 3.147 |
Call Number |
UA @ lucian @ c:irua:23985 |
Serial |
338 |
Permanent link to this record |
|
|
|
Author |
Verberck, B.; Michel, K.H.; Nikolaev, A.V. |
Title |
Crystal structures of polymerized fullerides AC60, A=K, Rb, Cs, and alkali-mediated interactions |
Type |
A1 Journal article |
Year |
2002 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
Volume |
116 |
Issue |
23 |
Pages |
10462-10474 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Starting from a model of rigid interacting C-60 polymer chains on an orthorhombic lattice, we study the mutual orientation of the chains and the stability of the crystalline structures Pmnn and I2/m. We take into account (i) van der Waals interactions and electric quadrupole interactions between C-60 monomers on different chains as well as (ii) interactions of the monomers with the surrounding alkali atoms. The direct interactions (i) always lead to an antiferrorotational structure Pmnn with alternate orientation of the C-60 chains in planes (001). The interactions (ii) with the alkalis consist of two parts: translation-rotation (TR) coupling where the orientations of the chains interact with displacements of the alkalis, and quadrupolar electronic polarizability (ep) coupling, where the electric quadrupoles on the C-60 monomers interact with induced quadrupoles due to excited electronic d-states of the alkalis. Both interactions (ii) lead to an effective orientation-orientation interaction between the C-60 chains and always favor the ferrorotational structure I2/m, where C-60 chains have a same orientation. The structures Pmnn for KC60 and I2/m for Rb- and CsC60 are the result of a competition between the direct interaction (i) and the alkali-mediated interactions (ii). In Rb- and CsC60 the latter are found to be dominant, the preponderant role being played by the quadrupolar electronic polarizability of the alkali ions. (C) 2002 American Institute of Physics. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000175905800044 |
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 |
2.965 |
Times cited |
12 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.965; 2002 IF: 2.998 |
Call Number |
UA @ lucian @ c:irua:103350 |
Serial |
578 |
Permanent link to this record |
|
|
|
Author |
Nikolaev, A.V.; Michel, K.H. |
Title |
Microscopic theory of the rhombohedral phase and transition to the monoclinic phase of solid C70 |
Type |
A1 Journal article |
Year |
1996 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
54 |
Issue |
18 |
Pages |
12733-12743 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Starting from a model of microscopic interactions between C-70 molecules, we have developed a theory which describes the orientational dynamics and its coupling to lattice displacements in the rhombohedral phase of C-70 fullerite. The Landau free energy is calculated. We obtain a first-order phase transition to a monoclinic structure with the space group P2(1)/m. The transition is driven by the condensation of orientational quadrupoles at the F point of the Brillouin zone of the rhombohedral lattice. We find no evidence that the monoclinic structure is connected with the freezing in of orientations around the fivefold molecular axis. We calculate the lattice strains that are associated with the transition to the monoclinic structure. The theory is compared with a range of experimental data on the phase transition. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
A1996VT68200028 |
Publication Date |
2002-07-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.736 |
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:16357 |
Serial |
2034 |
Permanent link to this record |
|
|
|
Author |
Nikolaev, A.V.; Lamoen, D.; Partoens, B. |
Title |
Extension of the basis set of linearized augmented plane wave (LAPW) method by using supplemented tight binding basis functions |
Type |
A1 Journal article |
Year |
2016 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
Volume |
145 |
Issue |
145 |
Pages |
014101 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
In order to increase the accuracy of the linearized augmented plane wave (LAPW) method, we present a new approach where the plane wave basis function is augmented by two different atomic radial components constructed at two different linearization energies corresponding to two different electron bands (or energy windows). We demonstrate that this case can be reduced to the standard treatment within the LAPW paradigm where the usual basis set is enriched by the basis functions of the tight binding type, which go to zero with zero derivative at the sphere boundary. We show that the task is closely related with the problem of extended core states which is currently solved by applying the LAPW method with local orbitals (LAPW+LO). In comparison with LAPW+LO, the number of supplemented basis functions in our approach is doubled, which opens up a new channel for the extension of the LAPW and LAPW+LO basis sets. The appearance of new supplemented basis functions absent in the LAPW+LO treatment is closely related with the existence of the ul-component in the canonical LAPW method. We discuss properties of additional tight binding basis functions and apply the extended basis set for computation of electron energy bands of lanthanum (face and body centered structures) and hexagonal close packed lattice of cadmium. We demonstrate that the new treatment gives lower total energies in comparison with both canonical LAPW and LAPW+LO, with the energy difference more pronounced for intermediate and poor LAPW basis sets. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
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Editor |
|
Language |
|
Wos |
000379584700003 |
Publication Date |
2016-07-05 |
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 |
2.965 |
Times cited |
11 |
Open Access |
|
Notes |
A.V.N. acknowledges useful discussions with B. Verberck, E. V. Tkalya, and A. V. Bibikov. |
Approved |
Most recent IF: 2.965 |
Call Number |
c:irua:134290 |
Serial |
4099 |
Permanent link to this record |
|
|
|
Author |
Nikolaev, A.V.; Michel, K.H. |
Title |
Symmetry lowering at the structural phase transitions in NpO2 and UO2 |
Type |
A1 Journal article |
Year |
2003 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
68 |
Issue |
5 |
Pages |
054112-054112,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The structural phase transitions with electric-quadrupole long-range order in NpO2 (Fm (3) over barm-->Pn (3) over barm) and UO2 (Fm (3) over barm-->Pa (3) over bar) are analyzed from a group theoretical point of view. In both cases, the symmetry lowering involves three quadrupolar components belonging to the irreducible representation T-2g (Gamma(5)) of O-h and condensing in a triple-q structure at the X point of the Brillouin zone. The Pa (3) over bar structure is close to Pn (3) over barm, but allows for oxygen displacements. The Pa (3) over bar ordering leads to an effective electrostatic attraction between electronic quadrupoles while the Pn (3) over barm ordering results in a repulsion between them. It is concluded that the Pn (3) over barm structure can be stabilized only through some additional process such as strengthening of the chemical bonding between Np and O. We also derive the relevant structure-factor amplitudes for Pn (3) over barm and Pa (3) over bar, and the effect of domains on resonant x-ray scattering experiments. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000185240100038 |
Publication Date |
2003-08-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
15 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2003 IF: NA |
Call Number |
UA @ lucian @ c:irua:94847 |
Serial |
3405 |
Permanent link to this record |
|
|
|
Author |
Nikolaev, A.V.; Michel, K.H. |
Title |
Superexchange and electron correlations in alkali fullerides AC60, A=K, Rb, Cs |
Type |
A1 Journal article |
Year |
2005 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
Volume |
122 |
Issue |
6 |
Pages |
064310-64314 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Superexchange interactions in alkali fullerides AC(60) are derived for C-60 molecular ions separated by interstitial alkali-metal ions. We use a multiconfiguration approach which comprises the lowest molecular orbital states of the C-60 molecule and the excited s and d states of the alkali-metal atom A. Interactions are described by the valence bond (Heitler-London) method for a complex (C-60 – A – C-60) – with two valence electrons. The electronic charge transfer between the alkali-metal atom and a neighboring C-60 molecule is not complete. The occupation probability of excited d and s states of the alkali atom is not negligible. In correspondence with the relative positions of the C-60 molecules and A atoms in the polymer crystal, we consider 180degrees and 90degrees (angle) superexchange pathways. For the former case the ground state is found to be a spin singlet separated from a triplet at similar to20 K. For T < 20 K there appear strong spin correlations for the 180degrees superexchange pathway. The results are related to spin lattice relaxation experiments on CsC60 in the polymerized and in the quenched cubic phase. (C) 2005 American Institute of Physics. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000226918100018 |
Publication Date |
2005-02-02 |
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 |
2.965 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.965; 2005 IF: 3.138 |
Call Number |
UA @ lucian @ c:irua:102740 |
Serial |
3377 |
Permanent link to this record |
|
|
|
Author |
Verberck, B.; Nikolaev, A.V.; Michel, K.H. |
Title |
Orientational charge density waves and the metal-insulator transition in polymerized KC60 |
Type |
A1 Journal article |
Year |
2005 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
71 |
Issue |
16 |
Pages |
165117-11 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A theoretical model is presented for the description of the metal-insulator transition which accompanies the structural phase transition at T approximate to 50 K in polymerized KC60. The model involves orientational charge density waves (along the C-60 polymer chains) which were introduced previously for a description of the structural phase transition. A satisfactory qualitative and quantitative understanding is obtained when the three-dimensionality of the crystal and the presence of the K+ counterions is properly taken into account. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000228763100035 |
Publication Date |
2005-04-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2005 IF: 3.185 |
Call Number |
UA @ lucian @ c:irua:104076 |
Serial |
2514 |
Permanent link to this record |
|
|
|
Author |
Verberck, B.; Nikolaev, A.V.; Michel, K.H. |
Title |
Theoretical model for the structural phase transition at the metal-insulator transition in polymerized KC60 |
Type |
A1 Journal article |
Year |
2002 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
Volume |
66 |
Issue |
16 |
Pages |
165425-165425,14 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The recently discovered structural transition in polymerized KC60 at about 50 K results in a doubling of the unit cell volume and accompanies the 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 small orientational charge density waves along the polymer chains and concomitant displacements of the surrounding K+ ions. The effect is specific for the space group Pmnn of KC60 and is absent in RbC60 and CsC60 (space group I2/m). The mechanism is relevant for the metal-insulator transition. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000179286400135 |
Publication Date |
2002-10-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
10 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2002 IF: NA |
Call Number |
UA @ lucian @ c:irua:94907 |
Serial |
3608 |
Permanent link to this record |
|
|
|
Author |
Michel, K.H.; Verberck, B.; Nikolaev, A.V. |
Title |
Anisotropic packing and one-dimensional fluctuations of C60 molecules in carbon nanotubes |
Type |
A1 Journal article |
Year |
2005 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
Volume |
95 |
Issue |
18 |
Pages |
185506-185506,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The confinement of a C-60 molecule encapsulated in a cylindrical nanotube depends on the tube radius. In small tubes with radius R-T less than or similar to 7 A, a fivefold axis of the molecule coincides with the tube axis. The interaction between C-60 molecules in the nanotube is then described by a O-2-rotor model on a 1D liquid chain with coupling between orientational and displacive correlations. This coupling leads to chain contraction. The structure factor of the 1D liquid is derived. In tubes with a larger radius the molecular centers of mass are displaced off the tube axis. The distinction of two groups of peapods with on- and off-axis molecules suggests an explanation of the apparent splitting of A(g) modes of C-60 in nanotubes measured by resonant Raman scattering. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000232887400041 |
Publication Date |
2005-10-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.462 |
Times cited |
40 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 8.462; 2005 IF: 7.489 |
Call Number |
UA @ lucian @ c:irua:94717 |
Serial |
127 |
Permanent link to this record |