E 43 Electronic structure and chemical bonding of delta-Bi203 / N. I. Medvedeva, V. P. Zhukov, D. L. Novikov, V. A. Gubanov // Journal of Structural Chemistry. - 1996. - Vol. 37, № 1. - P41-50 : il. - Bibliogr. : p. 49-50 (21 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ОКСИД ВИСМУТА -- ФЛЮОРИТОПОДОБНАЯ СТРУКТУРА -- ЛМТО МЕТОД Аннотация: The band structure of the fluorite-type 6-Bi203 was calculated by the linear LMTO methods in the approximation of overlapping atomic spheres using the basis set of orthogonal orbitals (LMTO-ASA) and by the full-potential LMTO method (LMTO-FP) for two vacancy orientations over a wide range of oxygen concentrations. The calculated parameters of chemical bonds - the binding energy Ebin and the pressure of the electron-nuclear system - show that the most stable compound is that with two vacancies per unit cell, oriented predominantly along the (111) direction. The hybrid Bi-O bonds are weak, and mostly the Bi-Bi bonds are responsible for the structural stabilization of c5-Bi203 . The mechanism of the formation of a semiconductor gap in the band structure of 6-Bi203 is discussed Полный текст |