Вид документа : Статья из журнала Шифр издания : 54/S 91 Автор(ы) : Suetin D. V., Shein I. R., Ivanovskii A. L. Заглавие : Structural,electronic properties and stability of tungsten mono- and semi-carbides:A first principles investigation Место публикации : Journal of Physics and Chemistry of Solids. - 2009. - Vol. 70. - С. P. 64-71: il. Примечания : Bibliogr. : p. 70-71 (49 ref.) ISSN: 0022-3697 ББК : 54 Предметные рубрики: ХИМИЧЕСКИЕ НАУКИ Ключевые слова (''Своб.индексиров.''): неорганические соединения--расчеты--структура кристаллическая--структура электронная--термодинамика Аннотация: First principles calculations have been performed with the purpose to understand the comparative peculiarities of the structural, electronic properties and stability for all phases formed in the tungsten–carbon system:hexagonal and cubic mono-carbides WC and four polymorphs(a, b, g and e) of semi-carbideW2C. All calculations were performed by means of the full-potential linearized augmented plane wave method FLAPW). The generalized gradient approximation(GGA)in the Perdew–Burke–Ernzerhof(PBE) formalism was used for the exchange and correlation energy functional. The geometries of all WC and W2C phases were optimized and their structural parameters and theoretical density were established. Besides,we have evaluated the formation energies(Eform) of all the tungsten carbides.Based on our estimations we can arrange all investigated W–C phases depending on??their stability in the following sequence: h-WC4e-W2C4b-W2C4g-W2C4a-W2C4c-WC.Here three carbides(h-WC, e-W2C and b-W2C) are stable(Eformo0), g-W2C belongs to metastable systems (Eform0), whereas a-W2C and c-WC appear to be unstable(Eform40). Moreover,band structures, total and partial densities of states were obtained and analyzedsystematically for all W–C phases in comparison with other availablet heoretical and experimental data Держатели документа: Центральная научная библиотека УрО РАН Доп.точки доступа: Shein, I. R.; Ivanovskii, A. L.