Grahlow Fabian, Strauß Fabian, Schmidt Patrick, Valenta Jaroslav, Ströbele Markus, Scheele Marcus, Romao Carl P, Meyer Hans-Jürgen
Section for Solid State and Theoretical Inorganic Chemistry, Institute of Inorganic Chemistry, Eberhard Karls Universität Tübingen, uf der Morgenstelle 18, Tübingen D-72076, Germany.
Institute of Physical and Theoretical Chemistry, Eberhard Karls Universität Tübingen, Tübingen D-72076, Germany.
Inorg Chem. 2024 Oct 21;63(42):19717-19727. doi: 10.1021/acs.inorgchem.4c02896. Epub 2024 Oct 7.
The compound TaSBr was prepared by a comproportionation reaction of tantalum bromide with tantalum and elemental sulfur. The crystal structure, as refined by single-crystal X-ray diffraction, is composed of clusters with TaS cores, arranged in corrugated van der Waals layers. Individual layers appear to be displaced relative to each other along one direction. Successful crystal growth in a melt of CsBr yielded black platelets of TaSBr, which were used to investigate the electrical properties of the compound. The electronic structure was studied by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy and by density functional theory (DFT) band structure calculations, revealing this material to be a small-gap semiconductor. DFT results, in combination with magnetic susceptibility measurements, suggest that metallicity originating from the one unpaired Ta d electron per cluster is most likely suppressed by electronic correlations, forming a cluster Mott insulator.
化合物TaSBr是通过溴化钽与钽和元素硫的归中反应制备的。经单晶X射线衍射精修后的晶体结构由具有TaS核的簇组成，排列成波纹状范德华层。各层似乎沿一个方向相互位移。在CsBr熔体中成功生长出TaSBr黑色片状晶体，用于研究该化合物的电学性质。通过漫反射红外傅里叶变换（DRIFT）光谱和密度泛函理论（DFT）能带结构计算研究了其电子结构，结果表明该材料是一种小带隙半导体。DFT结果与磁化率测量结果相结合表明，每个簇中一个未配对的Ta d电子产生的金属性很可能被电子关联所抑制，从而形成簇状莫特绝缘体。
