Records |
Author |
Nikolaev, A.V.; Verberck, B.; Ionova, G.V. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
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 |
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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 |
000274720000011 |
Publication Date |
2009-04-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0020-7608;1097-461X; |
ISBN |
|
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 |
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Author |
Michel, K.H.; Verberck, B.; Nikolaev, A. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
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 |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
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 |
Bousige, C.; Rols, S.; Cambedouzou, J.; Verberck, B.; Pekker, S.; Kováts, É.; Durkó, G.; Jalsovsky, I.; Pellegrini, É.; Launois, P. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
Lattice dynamics of a rotor-stator molecular crystal: Fullerene-cubane C60\centerdot C8H8 |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
82 |
Issue |
19 |
Pages |
195413-195413,10 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The dynamics of fullerene-cubane (C60⋅C8H8) cocrystal is studied combining experimental [x-ray diffuse scattering, quasielastic and inelastic neutron scattering (INS)] and simulation (molecular dynamics) investigations. Neutron scattering gives direct evidence of the free rotation of fullerenes and of the libration of cubanes in the high-temperature phase, validating the rotor-stator description of this molecular system. X-ray diffuse scattering shows that orientational disorder survives the order/disorder transition in the low-temperature phase, although the loss of fullerene isotropic rotational diffusion is featured by the appearance of a 2.2 meV mode in the INS spectra. The coupling between INS and simulations allows identifying a degeneracy lift of the cubane librations in the low temperature phase, which is used as a tool for probing the environment of cubane in this phase and for getting further insights into the phase transition mechanism. |
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 |
000283923500004 |
Publication Date |
2010-11-08 |
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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
16 |
Open Access |
|
Notes |
; The authors acknowledge P.-A. Albouy and S. Rouziere (LPS, Orsay) for fruitful discussions and for their support during diffuse scattering experiments. Work in Hungary was supported by the Hungarian Research Fund, OTKA under Grant No. K72954. The CS group at the ILL is acknowledged for their support during the MD simulations. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:85801 |
Serial |
1802 |
Permanent link to this record |
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Author |
Tyutyunnik, A.P.; Slobodin, B.V.; Samigullina, R.F.; Verberck, B.; Tarakina, N.V. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
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 |
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Series Issue |
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Edition |
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ISSN |
1477-9226;1477-9234; |
ISBN |
|
Additional Links |
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 |
Varykhalov, A.; Marchenko, D.; Sanchez-Barriga, J.; Scholz, M.R.; Verberck, B.; Trauzettel, B.; Wehling, T.O.; Carbone, C.; Rader, O. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
Intact dirac cones at broken sublattice symmetry : photoemission study of graphene on Ni and Co |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review X |
Abbreviated Journal |
Phys Rev X |
Volume |
2 |
Issue |
4 |
Pages |
041017-10 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The appearance of massless Dirac fermions in graphene requires two equivalent carbon sublattices of trigonal shape. While the generation of an effective mass and a band gap at the Dirac point remains an unresolved problem for freestanding extended graphene, it is well established by breaking translational symmetry by confinement and by breaking sublattice symmetry by interaction with a substrate. One of the strongest sublattice-symmetry-breaking interactions with predicted and measured band gaps ranging from 400 meV to more than 3 eV has been attributed to the interfaces of graphene with Ni and Co, which are also promising spin-filter interfaces. Here, we apply angle-resolved photoemission to epitaxial graphene on Ni (111) and Co(0001) to show the presence of intact Dirac cones 2.8 eV below the Fermi level. Our results challenge the common belief that the breaking of sublattice symmetry by a substrate and the opening of the band gap at the Dirac energy are in a straightforward relation. A simple effective model of a biased bilayer structure composed of graphene and a sublattice-symmetry-broken layer, corroborated by density-functional-theory calculations, demonstrates the general validity of our conclusions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
College Park, Md |
Editor |
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Language |
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Wos |
000312703200001 |
Publication Date |
2012-12-22 |
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 |
2160-3308; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.789 |
Times cited |
86 |
Open Access |
|
Notes |
; A. V. acknowledges helpful discussions with N. Sandler. This work was supported by SPP 1459 of the Deutsche Forschungsgemeinschaft. B. V. acknowledges support from the Research Foundation Flanders (FWO-Vlaanderen). B. T. and T. O. W. would like to thank the KITP at Santa Barbara for hospitality during the completion of this work. ; |
Approved |
Most recent IF: 12.789; 2012 IF: 6.711 |
Call Number |
UA @ lucian @ c:irua:105964 |
Serial |
1677 |
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 ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
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 |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.35 |
Times cited |
6 |
Open Access |
|
Notes |
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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 |
Verberck, B.; Michel, K.H.; Nikolaev, A.V. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
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 |
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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 |
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Author |
Verberck, B.; Michel, K.H. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
Anisotropic packing of C-70 molecules in carbon nanotubes |
Type |
A1 Journal article |
Year |
2007 |
Publication |
Physica status solidi B-basic solid state physics |
Abbreviated Journal |
Phys Status Solidi B |
Volume |
244 |
Issue |
11 |
Pages |
4279-4282 |
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 |
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Editor |
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Language |
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Wos |
000251355800092 |
Publication Date |
2007-10-19 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-1972;1521-3951; |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
1.674 |
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: 1.674; 2007 IF: 1.071 |
Call Number |
UA @ lucian @ c:irua:67350 |
Serial |
128 |
Permanent link to this record |
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Author |
Michel, K.H.; Verberck, B.; Nikolaev, A.V. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
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 |
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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 |
000232887400041 |
Publication Date |
2005-10-28 |
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 |
0031-9007;1079-7114; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.462 |
Times cited |
40 |
Open Access |
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Notes |
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Approved |
Most recent IF: 8.462; 2005 IF: 7.489 |
Call Number |
UA @ lucian @ c:irua:94717 |
Serial |
127 |
Permanent link to this record |
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Author |
Verberck, B.; Cambedouzou, J.; Vliegenthart, G.A.; Gompper, G.; Launois, P. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
A Monte Carlo study of C70 molecular motion in C70@SWCNT peapods |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
Volume |
49 |
Issue |
6 |
Pages |
2007-2021 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We present Monte Carlo simulations of chains of C70 molecules encapsulated in a single-walled carbon nanotube (SWCNT). For various tube radii R (6.5 Å less-than-or-equals, slant R less-than-or-equals, slant 7.5 Å), we analyze rotational and translational motion of the C70 molecules, as a function of temperature. Apart from reproducing the experimentally well-established lying and standing molecular orientations for small and large tube radii, respectively, we observe, depending on the tube diameter, a variety of molecular motions, orientational flipping of lying molecules, and the migration of molecules resulting in a continual rearrangement of the C70 molecules in clusters of varying lengths. With increasing temperature, the evolution of the pair correlation functions reveals a transition from linear harmonic chain behavior to a hard-sphere liquid, making C70@SWCNT peapods tunable physical realizations of two well-known one-dimensional model systems. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000288689900025 |
Publication Date |
2011-01-20 |
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 |
0008-6223; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.337 |
Times cited |
10 |
Open Access |
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Notes |
; Helpful discussions with K.H. Michel, P.-A. Albouy and C. Bousige are greatly acknowledged. This work was financially supported by the Research Foundation – Flanders (FWO-Vl). B.V. is a Postdoctoral Fellow of the Research Foundation Flanders (FWO-VI). ; |
Approved |
Most recent IF: 6.337; 2011 IF: 5.378 |
Call Number |
UA @ lucian @ c:irua:89660 |
Serial |
2201 |
Permanent link to this record |