The First-principles Study on the Optical Anisotropy of R3 Space Group Chalcogenides AX2MQ6  

作　　者：余桔颂 林华 郑宇君 吴新涛 吴立明 

机构地区：[1]Key Laboratory of Optoelectronic Materials Chemistry and Physics,Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences [2]University of Chinese Academy of Sciences

出　　处：《Chinese Journal of Structural Chemistry》2017年第9期1552-1561,共10页结构化学（英文）

基　　金：supported by the National Natural Science Foundation of China(Nos.21233009,90922021,20773130,20733003,20803080,20973175);the“Knowledge Innovation Program of the Chinese Academy of Sciences”(KJCX2-YW-H20,CXJJ-11-M71)

摘　　要：In order to explain the opposite phase matchability of two types of newly discovered chalcogenides, AX2MQ6 vs AX4M5Q12 belonging to the same R3 space group, the linear and nonlinear optical properties are calculated. The calculated Electron Localization Function（ELF） show the acentricity of the bonds on the Q^2- ions with sp^3 hybridization is the main origin of the optical anisotropy. To quantify such an acentricity, a geometric parameter, the dihedral angle between the tetrahedral undersides and the xy-planes is defined. And the calculated birefringence depends on the above defined geometric parameter and the ion radius. This correlation reasonably explains the opposite phase matchability of two closely related chalcogenide families of AX2MQ6 and AX4M5Q12 and is shedding useful light on further exploration on phase matchable IR-NLO crystals.In order to explain the opposite phase matchability of two types of newly discovered chalcogenides, AX2MQ6 vs AX4M5Q12 belonging to the same R3 space group, the linear and nonlinear optical properties are calculated. The calculated Electron Localization Function（ELF） show the acentricity of the bonds on the Q^2- ions with sp^3 hybridization is the main origin of the optical anisotropy. To quantify such an acentricity, a geometric parameter, the dihedral angle between the tetrahedral undersides and the xy-planes is defined. And the calculated birefringence depends on the above defined geometric parameter and the ion radius. This correlation reasonably explains the opposite phase matchability of two closely related chalcogenide families of AX2MQ6 and AX4M5Q12 and is shedding useful light on further exploration on phase matchable IR-NLO crystals.

关 键 词：nonlinear optical property BIREFRINGENCE phase matchability CHALCOGENIDES 

分 类 号：O611.2[理学—无机化学] O734[理学—化学]