Li Xiaoshuang, Liang Fei, Liu Tianpeng, Li Haifeng
School of Applied Physics and Materials, Wuyi University, Jiangmen, Guangdong 529020, P.R. China.
Dalton Trans. 2021 Aug 28;50(32):11167-11172. doi: 10.1039/d1dt01099a. Epub 2021 Jul 30.
By introducing halogens to the A/Ga/Q (A = Na, K; Q = S, Se) system, one new chalcohalide namely NaGaSCl was successfully obtained. It crystallizes in the orthorhombic space group Cmcm (63). NaGaSCl has a layered structure consisting of two dimensional [GaS] layers which are stacked in "face to face" and "back to back" arrays and separated by Na and Cl ions. Interestingly, supertetrahedral building units [GaS] (T2) which are rarely found in metal chalcogenides and metal chalcohalides are formed in this structure. Moreover, the distances of two adjacent layers are around four times larger than the ionic radius of the Na ion, which is very likely to provide a perfect environment for the storage and migration of Na ions. In particular, the volume concentration of the Na cations in this compound is as high as 1.54 × 10 cm. The UV-vis-NIR spectroscopy measurement reveals that the optical band gap of this title compound is 3.06 eV. The electronic structural calculations on NaGaSCl show that the band gap is mainly determined by the [GaS] groups and Na-Cl ionic bonding.
通过将卤素引入A/Ga/Q（A = Na、K；Q = S、Se）体系，成功获得了一种新的硫卤化物，即NaGaSCl。它结晶于正交空间群Cmcm（63）。NaGaSCl具有层状结构，由二维[GaS]层组成，这些层以“面对面”和“背靠背”的阵列堆叠，并由Na和Cl离子分隔。有趣的是，在这种结构中形成了在金属硫族化物和金属硫卤化物中很少发现的超四面体结构单元[GaS]（T2）。此外，两个相邻层之间的距离大约是Na离子离子半径的四倍，这很可能为Na离子的存储和迁移提供一个理想的环境。特别地，该化合物中Na阳离子的体积浓度高达1.54×10 cm。紫外-可见-近红外光谱测量表明，该标题化合物的光学带隙为3.06 eV。对NaGaSCl的电子结构计算表明，带隙主要由[GaS]基团和Na-Cl离子键决定。
