We report ab initio configuration interaction calculations of the optical properties of a neutral oxygen vacancy in Ge-doped silica. This defect center, V(SiGe), is assumed to involve a missing O atom between a Si and a Ge atom with formation of a direct Si-Ge bond, =Si-Ge=. Several calculations have been performed using cluster models to obtain a reliable estimate of the excitation energy. The lowest fully allowed singlet-singlet transition in V(SiGe) occurs in a spectral region around 7.3 eV according to the calculations, i.e. not too far from the absorption band at 7.6 eV attributed to a V(SiSi) center in pure silica. The emission properties of V(SiGe) and the reasons for the similar transition energy in V(SiSi) and V(SiGe) centers are discussed. (C) 1999 Elsevier Science B.V. All rights reserved
Pacchioni, G., Basile, A. (1999). First principle calculations of the optical properties of a neutral oxygen vacancy in Ge-doped silica. JOURNAL OF NON-CRYSTALLINE SOLIDS, 254(1-3), 17-25 [10.1016/S0022-3093(99)00369-5].
First principle calculations of the optical properties of a neutral oxygen vacancy in Ge-doped silica
Pacchioni, G;
1999
Abstract
We report ab initio configuration interaction calculations of the optical properties of a neutral oxygen vacancy in Ge-doped silica. This defect center, V(SiGe), is assumed to involve a missing O atom between a Si and a Ge atom with formation of a direct Si-Ge bond, =Si-Ge=. Several calculations have been performed using cluster models to obtain a reliable estimate of the excitation energy. The lowest fully allowed singlet-singlet transition in V(SiGe) occurs in a spectral region around 7.3 eV according to the calculations, i.e. not too far from the absorption band at 7.6 eV attributed to a V(SiSi) center in pure silica. The emission properties of V(SiGe) and the reasons for the similar transition energy in V(SiSi) and V(SiGe) centers are discussed. (C) 1999 Elsevier Science B.V. All rights reserved
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