From oxides to oxysulfides: the mixed-anion GeS3O unit induces huge improvement in the nonlinear optical effect and optical anisotropy for potential nonlinear optical materials

Xinyu Tian; Xiaodong Zhang; Yan Xiao; Xiaowen Wu; Bingbing Zhang; Daqing Yang; Kui Wu

doi:10.1039/d2ra02605h

From oxides to oxysulfides: the mixed-anion GeS₃O unit induces huge improvement in the nonlinear optical effect and optical anisotropy for potential nonlinear optical materials

RSC Adv. 2022 Jun 1;12(25):16296-16300. doi: 10.1039/d2ra02605h. eCollection 2022 May 23.

Authors

Xinyu Tian¹, Xiaodong Zhang¹, Yan Xiao¹, Xiaowen Wu¹, Bingbing Zhang¹, Daqing Yang¹, Kui Wu¹

Affiliation

¹ College of Chemistry and Environmental Science, Hebei University Baoding China wuxiaowen1114@163.com wukui@hbu.edu.cn.

Abstract

Oxysulfides combining intrinsic performance advantages between sulfides (strong NLO response) and oxides (wide optical bandgap) are proposed as potential infrared (IR) NLO materials. Theoretical calculation shows that the mixed-anion GeS₃O tetrahedron has a stronger polarizability anisotropy and hyperpolarizability than that of the typical GeO₄ unit. Based on this, two Sr₂MGe₂S₆O (M = Zn, Cd) oxysulfides with the GeS₃O unit show dozens of times improvement in critical birefringence and the NLO effect compared with those of isostructural Sr₂ZnGe₂O₇. Moreover, structure-property study further verifies that the mixed-anion GeS₃O ligand is a useful NLO-active unit and can offer great influence over the NLO origin. This research result also gives us a feasible design strategy and research system to explore new IR NLO candidates.