Modeling of the Non-Linear Optical Properties of the [GeO4] Centers in Silica

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Department of Physics


Semi-empirical PM3 calculations are performed on the Ge centers in silica using a cluster approximation in the Hartree-Fock framework. Ge-doped silica is simulated as a cluster that consists of a GeO4 unit together with its four nearest SiO4 units. Electron trapping does distort the local symmetry of the Ge center where the GeO4 unit is not exactly tetrahedral. The calculations of the microscopic NLO properties in terms of static hyperpolarizabilities show a large, noticeable increase in β related to second-harmonic generation or Kerr effect for the Ge(1) center upon electron trapping.

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© 1994

Publication Title

Journal of Non-Crystalline Solids