标题：Ba3GeS5and Ba3InS4Cl: Interesting size effects originated from the tetrahedral anions
作者：Pan, Ming-Yan ;Xia, Sheng-Qing ;Liu, Xiao-Cun ;Tao, Xu-Tang
作者机构：[Pan, Ming-Yan ;Xia, Sheng-Qing ;Liu, Xiao-Cun ;Tao, Xu-Tang ] State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong Uni 更多
来源：Journal of Solid State Chemistry
摘要：Two new barium chalcogenides, Ba3GeS5and Ba3InS4Cl, were synthesized by using high temperature solid-state reactions and their structures were determined by single-crystal X-ray diffraction technique. Despite the similar chemical formula, the structures of Ba3GeS5and Ba3InS4Cl are subtly different due to the size effects originated from the tetrahedral anions. Ba3GeS5crystallizes in the orthorhombic space group Pnma (no. 62) with cell parameters of a=12.0528(9) A˚, b=9.5497(7) A˚ and c=8.5979(6) A˚, while Ba3InS4Cl adopts a different tetragonal system (space group: I4/mcm, no. 140, a=b=8.3613(6) A˚, c=14.3806(18) A˚). The measured optical band gap of Ba3GeS5is 3.0 eV, a little smaller than the value of 3.42 eV in Ba3InS4Cl. Theoretical calculations by Wien2k are provided as well in order to better understand these results. © 2014 Elsevier Inc.