Department of Applied Chemistry, National Chiao Tung University , 1001 University Road, Hsinchu 30010, Taiwan.
Inorg Chem. 2014 Jan 6;53(1):80-4. doi: 10.1021/ic4013763. Epub 2013 Dec 23.
New ternary polyselenides Ba3TM2Se9 (TM = Nb, Ta) were synthesized through a solid-state reaction, and their structures were characterized using single-crystal X-ray diffraction. These compounds crystallized into a new structural type with a monoclinic space group P21/c. The structures were constructed from distorted, close-packed layers of ∞3[BaSe3]3.33– that incorporated TM atoms at octahedral sites and contained [(TM5+)2(Se2–)7(Se22–)] units. Diffuse reflectance spectra and electronic resistivity measurements indicated semiconducting properties and optical band gaps of 1.3 eV for Ba3Nb2Se9 and 1.6 eV for Ba3Ta2Se9. Raman spectra were used to investigate the interatomic interactions. Calculations of the electronic structure verified the semiconducting behavior and bonding interaction of short Se–Se contacts.
通过固态反应合成了新的三元硒化物 Ba3TM2Se9（TM = Nb，Ta），并通过单晶 X 射线衍射对其结构进行了表征。这些化合物结晶为具有单斜空间群 P21/c 的新结构类型。结构由扭曲的、紧密堆积的 ∞3[BaSe3]3.33-层组成，其中 TM 原子占据八面体位置，包含[(TM5+)2(Se2–)7(Se22–)]单元。漫反射光谱和电子电阻率测量表明 Ba3Nb2Se9 和 Ba3Ta2Se9 具有半导体性质和 1.3 eV 和 1.6 eV 的光学带隙。拉曼光谱用于研究原子间相互作用。电子结构的计算验证了短 Se–Se 接触的半导体行为和键合相互作用。
