On the orientational relief of the intermolecular potential and the structure of domain walls in fullerite C₆₀

• Datum: 2003
• Hauptverfasser: Khalack, J.M., Loktev, V.M.
• Format: Artikel
• Sprache: English
• Veröffentlicht: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 2003
• Schriftenreihe: Физика низких температур
• Schlagworte: Динамика кристаллической решетки
• Online Zugang: https://nasplib.isofts.kiev.ua/handle/123456789/128850
• Назва журналу: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Zitieren: On the orientational relief of the intermolecular potential and the structure of domain walls in fullerite C₆₀ / J.M. Khalack, V.M. Loktev // Физика низких температур. — 2003. — Т. 29, № 5. — С. 577-589. — Бібліогр.: 25 назв. — англ.

A simple planar model for an orientational ordering of threefold molecules on a triangular lattice modeling a close-packed (111) plane of fullerite is considered. The system has 3-sublattice ordered ground state which includes 3 different molecular orientations. There exist 6 kinds of orientational domains, which are related with a permutation or a mirror symmetry. Interdomain walls are found to be rather narrow. The model molecules have two-well orientational potential profiles, which are slightly effected by a presence of a straight domain wall. The reason is a stronger correlation between neighbor molecules in the triangular lattice versus the square lattice previously considered. A considerable reduction (up to one order) of the orientational interwell potential barrier is found in the core regions of essentially two-dimentional potential defects, such as a three-domain boundary or a kink in the domain wall. For ultimately uncorrelated nearest neighbors the height of the interwell barrier can be reduced even by a factor of 10².