E 58 Enyashin, A. N. Structural, electronic, cohesive, and elastic properties of diamondlike allotropes of crystalline C40 [Текст] / A. N. Enyashin, A. L. Ivanovskii // Physical Review B: Condensed Matter and Materials Physics. - 2008. - Vol. 77, № 11. - С. 113402/1-113402/4. - Библиогр. : с. 113402/4 (21 назв.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): АЛЛОТРОПИЯ -- АЛМАЗОПОДОБНЫЕ КРИСТАЛЛЫ -- ФУЛЛЕРЕНЫ Аннотация: The atomic models of diamondlike allotropes of crystalline C40 hyperdiamond, hyperlonsdaleite and socalled autointercalated hyperdiamond are offered and using the density-functional based tight-binding method their structural, cohesive, elastic, and electronic properties are predicted as well as their theoretical x-ray diffraction spectra are derived. Among these allotropes the autointercalated hyperdiamond C40 has a unique combined type of both covalent and van der Waals bonding and shows the highest density and hardness Полный текст |
C 73 Computer Design of Novel Diamond-Like Crystals of Fullerenes C28 and C40: Stability, Crystal Structure, and Elastic and Electronic Properties / A. N. Enyashin, V. L. Bekenev, L. I. Ovsyannikova, Yu. I. Rogovoi, A. V. Pokropivny, V. V. Pokropivny, A. L. Ivanovskii // Nanotechnologies in Russia. - 2008. - Vol. 3, № 1. - P79-84 : il. - Bibliogr. : p. 84 (14 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): АЛМАЗОПОДОБНЫЕ КРИСТАЛЛЫ -- ФУЛЛЕРЕНЫ Аннотация: Novel dense crystalline modifications of small Cn fullerenes (n= 28, 40), i.e., the so-called autointercalated hyperdiamonds with combined covalent and van der Waals types of Cn–Cn interatomic bonds, are proposed and simulated. The crystal structures of these modifications consist of Cn fullerene molecules forming diamond lattices in which holes are occupied by the same fullerene molecules. The crystal structures, elastic and electronic properties, and energies of formation of the Cn autointercalated hyperdiamonds are calculated using the ensity-functional-based tight-binding (DFTB) method. The bulk moduli of the autointercalated hyperdiamonds are found to increase abruptly as compared to those of the initial hyperdiamonds. It is established that the C28 and C40 autointercalated hyperdiamonds are semiconductors with the band gaps approximately equal to 1.30 and 0.94 eV, respectively |