Abudurusuli Ailijiang, Li Junjie, Tong Tinghao, Yang Zhihua, Pan Shilie
CAS Key Laboratory of Functional Materials and Devices for Special Environments, Xinjiang Technical Institute of Physics & Chemistry, CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, 40-1 South Beijing Road, Urumqi 830011, People's Republic of China.
Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
Inorg Chem. 2020 Apr 20;59(8):5674-5682. doi: 10.1021/acs.inorgchem.0c00431. Epub 2020 Apr 4.
The exploration of novel infrared nonlinear optical (IR NLO) materials with large second-harmonic generation (SHG) responses and wide band gaps has become very imperative recently. Herein we reported two noncentrosymmetric compounds, LiBaGaQ (Q = S, Se), crystallizing in space group 42 (No. 114), which feature 3D frameworks built by a basic [GaQ] windmill cluster and LiQ tetrahedra in a cesium chloride topological structure. Both compounds satisfy the desired balance between good SHG responses (∼1.5× that of AgGaS) and wide band gaps (3.43 and 2.44 eV) with remarkable laser damage thresholds (21× and 6× that of AgGaS). The theoretical calculations uncover that the [GaQ] cluster makes major contributions to the SHG effect in LiBaGaQ. In addition, the structure-performance relationship among all compounds in the I-II-III-VI system has been discussed systematically, which indicates that the introduction of the alkali metal lithium in the I site is beneficial for the production of large band gaps. This work will be helpful in exploring novel IR NLO materials with special structures and comprehensive properties in the chalcogenide system.
最近，探索具有大二次谐波产生（SHG）响应和宽带隙的新型红外非线性光学（IR NLO）材料变得非常迫切。在此，我们报道了两种非中心对称化合物LiBaGaQ（Q = S，Se），它们结晶于空间群42（编号114），其特征是由基本的[GaQ]风车簇和LiQ四面体在氯化铯拓扑结构中构建的三维框架。这两种化合物在良好的SHG响应（约为AgGaS的1.5倍）和宽带隙（3.43和2.44 eV）之间实现了所需的平衡，并且具有显著的激光损伤阈值（分别为AgGaS的21倍和6倍）。理论计算表明，[GaQ]簇对LiBaGaQ中的SHG效应起主要作用。此外，还系统地讨论了I-II-III-VI体系中所有化合物的结构-性能关系，这表明在I位引入碱金属锂有利于产生大的带隙。这项工作将有助于在硫族化物体系中探索具有特殊结构和综合性能的新型IR NLO材料。
