Halogen-assisted octet binding electrons construction of pnictogens towards wide-bandgap nonlinear optical pnictides  

作　　者：Lihua Gao Yinglei Han Chensheng Lin Huikang Jiang Guang Peng Guangsai Yang Jindong Chen Ning Ye 

机构地区：[1]Tianjin Key Laboratory of Functional Crystal Materials,Institute of Functional Crystals,Materials Science and Engineering,Tianjin University of Technology,Tianjin 300384,China [2]MOE Key Laboratory of Weak-Light Nonlinear Photonics,School of Physical Sciences,Nankai University,Tianjin 300457,China [3]Key Laboratory of Optoelectronic Materials Chemistry and Physics,Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences,Fuzhou 350002,China [4]Tianjin Key Laboratory of Quantum Optics and Intelligent Photonics,School of Science,Tianjin University of Technology,Tianjin 300384,China

出　　处：《Chinese Chemical Letters》2024年第12期557-560,共4页中国化学快报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.22305174,22375147,52332001,51890862,51902308 and 21921001);the Natural Science Foundation of Fujian Province(No.2021J05097);the Natural Science Foundation of Tianjin City(No.22JCYBJC01380)。

摘　　要：The design of pnictide nonlinear optical crystals is quite different from chalcogenide and oxide those in which a new paradigm need be developed to regulate the band gap,one of key optical parameters In this work,two non-centrosymmetric halidepnictides,[Cd_(2)P]_(2)[CdBr_(4)](CPB)and[Cd_(2)As]_(2)[CdBr_(4)](CAB) were reported.The complete octet binding electrons of pnictogens were constructed by four Cd-P pola covalent bonds under the anchoring effect of halogens,creating an extremely flat valence band maximum with band dispersion of only 0.17 eV.As expected,the balance of the covalency and ionicity in CPB and CAB was successfully realized,leading to a wide band gap of 2.58 eV and 1.88 eV.Remarkably,CPB no only has a widest band gap among Cd-containing pnictides,but also exhibits a SHG effect of 1.2×AgGaS_(2).moderate birefringence(0.088@visible light and calcd.0.043@2050 nm)and a wide IR transmission range.This is the first time that the octet binding electrons construction strategy was utilized to design non diamond like NLO pnictides with excellent performances.

关 键 词：Nonlinear optical crystal Halidepnictide Wide band gap Structure design Electronic structure 

分 类 号：O734[理学—晶体学]