Theoretical Third-Order Hyperpolarizability of Paratellurite from the Finite Field Perturbation Method

Density functional theory was used to estimate the third-order hypersusceptibility χ(3) of the α-TeO2 paratellurite (as a model structure for TeO2 glass) and the same value for α-SiO2 cristobalite (as a model structure for glassy silica). The attempt was made to gain a physical insight into the nature of the extraordinarily high hypersusceptibility of TeO2 glass. A finite field perturbation method implemented in the CRYSTAL code with the “sawtooth” approach was employed. The χ(3) values calculated for α-TeO2 were found to be of the same order as that measured for TeO2 glass and much higher than the values computed for α-SiO2 which, in turn, were close to that of glassy silica.