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Title: Ab initio structural, electronic and optical properties of orthorhombic CaGeO{sub 3}

Abstract

Orthorhombic CaGeO{sub 3} is studied using density-functional theory (DFT) considering both the local density and generalized gradient approximations, LDA and GGA, respectively. The electronic band structure, density of states, dielectric function and optical absorption are calculated. Two very close indirect (S->{gamma}) and direct ({gamma}->{gamma}) band gap energies of 1.68eV (2.31eV) and 1.75eV (2.41eV) were obtained within the GGA (LDA) approximation, as well as the effective masses for electrons and holes. Comparing with orthorhombic CaCO{sub 3} (aragonite), the substitution of carbon by germanium changes the localization of the valence band maximum of the indirect transition, and decreases by almost 2.0eV the Kohn-Sham band gap energies.

Authors:
 [1];  [2];  [3];  [3];  [1]
  1. Departamento de Fisica Teorica e Experimental, Universidade Federal do Rio Grande do Norte, 59072-900 Natal, Rio Grande do Norte (Brazil)
  2. Centro Federal de Educacao Tecnologica do Ceara, Avenida 13 de Maio, 2081, Benfica, 60040-531 Fortaleza, Ceara (Brazil), E-mail: ewcaetano@gmail.com
  3. Departamento de Fisica, Universidade Federal do Ceara, Centro de Ciencias, Caixa Postal 6030, Campus do Pici, 60455-760 Fortaleza, Ceara (Brazil)
Publication Date:
OSTI Identifier:
21015736
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 180; Journal Issue: 3; Other Information: DOI: 10.1016/j.jssc.2006.12.029; PII: S0022-4596(07)00005-9; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ABSORPTION; ARAGONITE; CALCIUM CARBONATES; DENSITY FUNCTIONAL METHOD; DIELECTRIC MATERIALS; GERMANATES; HOLES; OPTICAL PROPERTIES; ORTHORHOMBIC LATTICES

Citation Formats

Henriques, J.M., Caetano, E.W.S., Freire, V.N., Costa, J.A.P. da, and Albuquerque, E.L. Ab initio structural, electronic and optical properties of orthorhombic CaGeO{sub 3}. United States: N. p., 2007. Web. doi:10.1016/j.jssc.2006.12.029.
Henriques, J.M., Caetano, E.W.S., Freire, V.N., Costa, J.A.P. da, & Albuquerque, E.L. Ab initio structural, electronic and optical properties of orthorhombic CaGeO{sub 3}. United States. doi:10.1016/j.jssc.2006.12.029.
Henriques, J.M., Caetano, E.W.S., Freire, V.N., Costa, J.A.P. da, and Albuquerque, E.L. Thu . "Ab initio structural, electronic and optical properties of orthorhombic CaGeO{sub 3}". United States. doi:10.1016/j.jssc.2006.12.029.
@article{osti_21015736,
title = {Ab initio structural, electronic and optical properties of orthorhombic CaGeO{sub 3}},
author = {Henriques, J.M. and Caetano, E.W.S. and Freire, V.N. and Costa, J.A.P. da and Albuquerque, E.L.},
abstractNote = {Orthorhombic CaGeO{sub 3} is studied using density-functional theory (DFT) considering both the local density and generalized gradient approximations, LDA and GGA, respectively. The electronic band structure, density of states, dielectric function and optical absorption are calculated. Two very close indirect (S->{gamma}) and direct ({gamma}->{gamma}) band gap energies of 1.68eV (2.31eV) and 1.75eV (2.41eV) were obtained within the GGA (LDA) approximation, as well as the effective masses for electrons and holes. Comparing with orthorhombic CaCO{sub 3} (aragonite), the substitution of carbon by germanium changes the localization of the valence band maximum of the indirect transition, and decreases by almost 2.0eV the Kohn-Sham band gap energies.},
doi = {10.1016/j.jssc.2006.12.029},
journal = {Journal of Solid State Chemistry},
number = 3,
volume = 180,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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