Two Tellurium(IV)-Based Sulfates Exhibiting Strong Second Harmonic Generation and Moderate Birefringence as Promising Ultraviolet Nonlinear Optical Materials
Yunxia Song, Xia Hao, Chensheng Lin, Donghong Lin, Min Luo, Ning Ye
Abstract
Two tellurium(IV)-based sulfate nonlinear optical (NLO) materials, Te2O3(SO4) and Te(OH)3(SO4)·H3O, were successfully synthesized via the mild hydrothermal method. Te2O3SO4 has a two-dimensional (2D) structure consisting of [Te6O12]∞ layers as well as [SO4] groups. Te(OH)3(SO4)·H3O features a simple 0D structure made up of an isolated [TeO3] pyramid and a [SO4] tetrahedra. Both of them are phase-matching materials and show remarkable powder second harmonic generation (SHG) efficiencies about 6 and 3 times that of KH2PO4 (KDP), respectively, for Te2O3SO4 and Te(OH)3(SO4)·H3O. Especially for Te(OH)3(SO4)·H3O, in addition to a large SHG response, it possesses a short UV cutoff edge (∼233 nm) as well as moderate birefringence ([email protected] nm). Furthermore, theoretical calculations confirmed that their strong SHG effects are due to the synergistic effect of the [TeO3] pyramid and [SO4] tetrahedra.