title: Synthesis, structure and bonding, optical properties of Ba₄MTrQ₆ (M=Cu, Ag; Tr=Ga, In; Q=S, Se).
abstract: Four new quaternary chalcogenides, Ba4AgGaS6 (1), Ba4AgGaSe6 (2), Ba4CuInS6 (3), and Ba4AgInS6 (4), were synthesized by solid-state reactions and their structures were characterized through single-crystal X-ray diffraction. In spite of their similar chemical compositions, the flexible arrangement between the transition metals and the triel atoms leads to subtle differences in their polyanion structures. All structures feature similar [MTrQ6](8-) 1D polyanionic chains (M=Cu, Ag; Tr=Ga, In; Q=S, Se), which are constructed from corner-sharing MQ4 or TrQ4 tetrahedra. However, the transition metals and triels are mixed in 1, 2, and 3, but they occupy independent crystallographic sites in 4. As a result, compounds 1-3 belong to the known Ba2CoS3 (Pnma No. 62) or Ba2 MnS3 (Pnma No. 62) class, whereas 4 crystallizes in its own structural type within the monoclinic P2₁/c (No. 14) space group. The structural relationship among these new phases was also studied with the aid of DFT calculations and related optical properties are presented as well.
authors: State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, Ji'nan, Shandong, 250100 (China), Fax: (+86) 531-88362519; Key Laboratory of Inorganic Chemistry in Universities of Shandong, Department of Chemistry and Chemical Engineering, Jining University, Qu'fu, Shandong, 273155 (China).
authors: Xiao-Wu
authors: XW
authors: Lei
authors: Min
authors: M
authors: Yang
authors: Sheng-Qing
authors: SQ
authors: Xia
authors: Xiao-Cun
authors: XC
authors: Liu
authors: Ming-Yan
authors: MY
authors: Pan
authors: Xin
authors: X
authors: Li
authors: Xu-Tang
authors: XT
authors: Tao
keywords: chalcogens; crystal structure; luminescence; transition metals