The recently developed maximum overlap symmetry crystal orbital method is employed to calculate directly the band structures and the corresponding density of states functions of NaxWO3 with x = 0, 0.5, 0.625, 0.75, 0.875 and 1, including the all-valence atomic orbitais. The calculated band gap of WO3 is 2.86 eV, which is close to the reported experimental value of 2.62 eV obtained from indirect optical measurements. The calculated band gap of cubic NaxWO3 increases by 0.49 eV in going from x = 0.5 to 1, which agrees qualitatively with the empirical formula of Wolfram and Sutcu for calculating the band gap, and with the results of optical measurements. The density of states functions obtained are applied to elucidating the X-ray photoelectron spectroscopy peaks and evaluating directly the electronic specific heat coefficient; and they allow us to understand qualitatively the x-dependence of these properties. All the calculated results are qualitatively in agreement with the experimental results, and illustrate the reasonableness of the simple Wolfram and Sutcu theory for describing the electronic properties of cubic NaxWO3.
|Number of pages||10|
|Journal||Journal of Molecular Structure: THEOCHEM|
|State||Published - Sep 1993|
Bibliographical noteFunding Information:
The project was supported by the National Natural Science Foundation of China and the excellenTt eacher’sF oundationo f the StateE duca-tion Commission of China. One of us (C.G.Z.) wishes to thank the Ministry of Education, Sciencea nd Culture of Japan for providingf inan-cial supportf or his visit to Japan; he wishesa lso to expressh is sinceret hanksto Profesor S. Iwata of Keio University,P rofessorY . Osamurao f Rikkyo University and all the memberso f Iwata Laboratory of Keio Universityf or their kind help.
ASJC Scopus subject areas
- Condensed Matter Physics
- Physical and Theoretical Chemistry