Huge susceptibility increase within the (1 x) TeO2 + x TeO3 crystal system: Ab initio calculation study

Abstract The ab initio calculations performed for the TeO 2  → Te 4 O 9  → Te 2 O 5  → TeO 3 series of crystal lattices have revealed that, in this series, the average χ 3 non-linear susceptibility increases for about 10 times. Such a huge effect is attributed to the strong augmentation of the Te atom d-function contributions in valence molecular orbitals, which accompanies the Te 4+  → Te 6+ transformation. The results obtained allow concluding that the TeO 3 -related materials can be of interest in non-linear optic device engineering.