Two new thiohalides Pb_(3)GeS_(4)Br_(2) and Pb_(3.5)GeS_(4)Br_(3) have been synthesized by introducing Pb^(2+)into the thiogermanate system.The compounds crystallize in centrosymmetric P2_(1)/c(Pb_(3)GeS_(4)Br_(2))and...Two new thiohalides Pb_(3)GeS_(4)Br_(2) and Pb_(3.5)GeS_(4)Br_(3) have been synthesized by introducing Pb^(2+)into the thiogermanate system.The compounds crystallize in centrosymmetric P2_(1)/c(Pb_(3)GeS_(4)Br_(2))and noncentrosymmetric P63(Pb_(3.5)GeS_(4)Br_(3))space groups,respectively.To the best of our knowledge,Pb_(3)GeS_(4)Br_(2) and Pb_(3.5)GeS_(4)Br_(3) are the first Pb-containing thiogermanate halides,and the latter is the first phase-matching IR nonlinear optical material in the thiogermanate halide system.Due to the presence of Pb^(2+)with stereochemically active lone pair electrons,Pb_(3)GeS_(4)Br_(2) exhibits a strong optical anisotropy with a birefringence of 0.131@1064 nm,while Pb_(3.5)GeS_(4)Br_(3) shows a large second-harmonic generation response(0.8×AgGaS_(2))and high laser-induced damage threshold(3.0×AgGaS_(2)).These results enrich the structural and chemical diversity of chalcohalides.展开更多
基金supported by the National Natural Science Foundation of China(61835014 and 51972336)the Xinjiang Tianshan Talent Program(2022TSYCTD0005)the Scientific Foundation of Binzhou Medical University(No.50012304488).
文摘Two new thiohalides Pb_(3)GeS_(4)Br_(2) and Pb_(3.5)GeS_(4)Br_(3) have been synthesized by introducing Pb^(2+)into the thiogermanate system.The compounds crystallize in centrosymmetric P2_(1)/c(Pb_(3)GeS_(4)Br_(2))and noncentrosymmetric P63(Pb_(3.5)GeS_(4)Br_(3))space groups,respectively.To the best of our knowledge,Pb_(3)GeS_(4)Br_(2) and Pb_(3.5)GeS_(4)Br_(3) are the first Pb-containing thiogermanate halides,and the latter is the first phase-matching IR nonlinear optical material in the thiogermanate halide system.Due to the presence of Pb^(2+)with stereochemically active lone pair electrons,Pb_(3)GeS_(4)Br_(2) exhibits a strong optical anisotropy with a birefringence of 0.131@1064 nm,while Pb_(3.5)GeS_(4)Br_(3) shows a large second-harmonic generation response(0.8×AgGaS_(2))and high laser-induced damage threshold(3.0×AgGaS_(2)).These results enrich the structural and chemical diversity of chalcohalides.
