Résumé
Density functional theory was used to estimate the third-order hypersusceptibility (3) of the R-TeO2 paratellurite (as a model structure for TeO2 glass) and the same value for R-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 (3) values calculated for R-TeO2 were found to be of the same order as that measured for TeO2 glass and much higher than the values computed for R-SiO2 which, in turn, were close to that of glassy silica.