Records |
Author |
Tyutyunnik, A.P.; Slobodin, B.V.; Samigullina, R.F.; Verberck, B.; Tarakina, N.V. |
Title |
K2CaV2O7 : a pyrovanadate with a new layered type of structure in the A2BV2O7 family |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
Dalton T |
Volume |
42 |
Issue |
4 |
Pages |
1057-1064 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The crystal structure of K2CaV2O7 prepared by a conventional solid-state reaction has been solved by a direct method and refined using Rietveld full profile fitting based on X-ray powder diffraction data. This compound crystallises in the triclinic space group (P (1) over bar, Z = 2) with unit cell constants a = 7.1577(1) angstrom, b = 10.5104(2) angstrom, c = 5.8187(1) angstrom, alpha = 106.3368(9)degrees, beta = 106.235(1)degrees, gamma = 71.1375(9)degrees. The structure can be described as infinite undulating CaV2O72- layers parallel to the ac plane, which consist of pairs of edge-sharing CaO6 octahedra connected to each other through V2O7 pyrogroups. The potassium atoms are positioned in two sites between the layers, with a distorted IX-fold coordination of oxygen atoms. The chemical composition obtained from the structural solution was confirmed by energy-dispersive X-ray analysis. The stability of compounds in the family of alkali metal calcium pyrovanadates is discussed based on an analysis of the correlation between anion and cation sizes and theoretical first-principles calculations. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000312659200030 |
Publication Date |
2012-10-04 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
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ISSN |
1477-9226;1477-9234; |
ISBN |
|
Additional Links ![sorted by Additional Links field, descending order (down)](img/sort_desc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.029 |
Times cited |
3 |
Open Access |
|
Notes |
; N.V.T. acknowledges funding by the Bavarian Ministry of Sciences, Research and the Arts. B. V. was financially supported by the Flemish Science Foundation (FWO-Vlaanderen). ; |
Approved |
Most recent IF: 4.029; 2013 IF: 4.097 |
Call Number |
UA @ lucian @ c:irua:105945 |
Serial |
3536 |
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 |
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 |
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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 |
000228763100035 |
Publication Date |
2005-04-27 |
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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links ![sorted by Additional Links field, descending order (down)](img/sort_desc.gif) |
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 |
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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 |
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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 |
000175905800044 |
Publication Date |
2002-07-26 |
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 |
|
Additional Links ![sorted by Additional Links field, descending order (down)](img/sort_desc.gif) |
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 |
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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 ![sorted by Additional Links field, descending order (down)](img/sort_desc.gif) |
UA library record; WoS full record |
Impact Factor |
1.35 |
Times cited |
|
Open Access |
|
Notes |
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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 |
Verberck, B.; Heresanu, V.; Rouziere, S.; Cambedouzou, J.; Launois, P.; Kovats, E.; Pekker, S.; Vliegenthart, G.A.; Michel, K.H.; Gompper, G. |
Title |
Fullerene-cubane : X-ray scattering experiments and Monte Carlo simulations |
Type |
A1 Journal article |
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 |
Volume |
16 |
Issue |
5-6 |
Pages |
293-300 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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. |
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 |
000259645200003 |
Publication Date |
2008-09-28 |
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 ![sorted by Additional Links field, descending order (down)](img/sort_desc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.35 |
Times cited |
6 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.35; 2008 IF: 0.680 |
Call Number |
UA @ lucian @ c:irua:102640 |
Serial |
1295 |
Permanent link to this record |
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Author |
Bousige, C.; Rols, S.; Paineau, E.; Rouziere, S.; Mocuta, C.; Verberck, B.; Wright, J.P.; Kataura, H.; Launois, P. |
Title |
Progressive melting in confined one-dimensional C60 chains |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
86 |
Issue |
4 |
Pages |
045446 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
C-60 fullerenes confined inside single-walled carbon nanotubes form an archetypal one-dimensional system. X-ray diffraction experiments, from room temperature to 1073 K, reveal an increasing melting phenomenon. Detailed analysis of the sawtooth peak characteristic of the fullerene organization allows the quantitative determination of fluctuations in intermolecular distances. The present results validate the predictions of one-dimensional statistical models. |
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 |
000306925300007 |
Publication Date |
2012-08-01 |
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 |
1098-0121;1550-235X; |
ISBN |
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Additional Links ![sorted by Additional Links field, descending order (down)](img/sort_desc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
|
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:100835 |
Serial |
2726 |
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 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 |
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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 |
000179286400135 |
Publication Date |
2002-10-30 |
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 |
0163-1829;1095-3795; |
ISBN |
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Additional Links ![sorted by Additional Links field, descending order (down)](img/sort_desc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
10 |
Open Access |
|
Notes |
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Approved |
Most recent IF: 3.836; 2002 IF: NA |
Call Number |
UA @ lucian @ c:irua:94907 |
Serial |
3608 |
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 |
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ISSN |
0094-243x |
ISBN |
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Additional Links ![sorted by Additional Links field, descending order (down)](img/sort_desc.gif) |
UA library record; WoS full record; |
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 |
Call Number |
UA @ lucian @ c:irua:94831 |
Serial |
2513 |
Permanent link to this record |
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Author |
Michel, K.H.; Verberck, B.; Nikolaev, A. |
Title |
Mercator maps of orientations of a C60 molecule in single-walled nanotubes with distinct radii |
Type |
A1 Journal article |
Year |
2005 |
Publication |
AIP conference proceedings |
Abbreviated Journal |
|
Volume |
786 |
Issue |
|
Pages |
69-72 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study the confinement of a C-60 molecule encapsulated in a cylindrical nanotube as a function of the tube radius. Drawing the Mercator maps of the potential, we find two distinct molecular orientations; for tubes with small radii, R-T less than or similar to 7 angstrom, a fivefold axis of the molecule coincides with the tube long axis, for larger radii, R-T less than or similar to 8 angstrom, a threefold axis of the molecule coincides with the tube long axis. These different orientations are caused by the relative importance of the repulsive and the attractive parts of the van der Waals potentials of the molecule with the tube wall for small and large tubes respectively. Experimental evidence is provided by the apparent splitting of A(g) modes of the C-60 molecule in resonant Raman scattering. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Amer inst physics |
Place of Publication |
Melville |
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 |
0094-243x |
ISBN |
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Additional Links ![sorted by Additional Links field, descending order (down)](img/sort_desc.gif) |
UA library record; WoS full record; |
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 |
Call Number |
UA @ lucian @ c:irua:94738 |
Serial |
1993 |
Permanent link to this record |
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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 |
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Edition |
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ISSN |
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ISBN |
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Additional Links ![sorted by Additional Links field, descending order (down)](img/sort_desc.gif) |
UA library record; WoS full record; |
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 |
Call Number |
UA @ lucian @ c:irua:36883 |
Serial |
3614 |
Permanent link to this record |