Bi3In4S10 and Bi14.7In11.3S38: Two new bismuth sulfides with interesting Bi–Bi bonding

Two new ternary bismuth chalcogenides, Bi3In4S10 and Bi14.7In11.3S38, were synthesized from the reactions of binary sulfides via a two-step flux technique. Single-crystal X-ray diffraction analyses indicate that Bi3In4S10 crystallizes in the non-centrosymmetric space group Pm and Bi14.7In11.3S38 crystallizes in the centrosymmetric space group P21/m. Both compounds adopt three-dimensional frameworks. A distinct structural feature in the two structures is the presence of chains of Bi atoms with alternating short Bi–Bi bonds of around 3.1 Å and longer distances of around 4.6 Å. The optical band gaps of 1.42(2) eV for Bi3In4S10 and 1.45(2) eV for Bi14.7In11.3S38 were deduced from the diffuse reflectance spectra.

Graphical abstractTwo new bismuth sulfides Bi3In4S10 and Bi14.7In11.3S38 have been synthesized and characterized. The figure is the arrangement of Bi1 atoms along the b direction with alternating short and long distances (Å) in Bi3In4S10.Figure optionsDownload full-size imageDownload as PowerPoint slide