Quaternary sulfide Ba5Cd2Ga2S10 containing chains of edge- and corner-sharing tetrahedra

Highlights: • Ba₅Cd₂Ga₂S₅ is the first quaternary phase in the Ba–Cd–Ga–S system. • It adopts a new structure type containing ordered Cd and Ga atoms within 1D-chains. • It has an optical band gap of 3.2 eV, consistent with yellow colour of Ba₅Cd₂Ga₂S₅. The quaternary sulfide Ba₅Cd₂Ga₂S₁₀ was prepared by reaction of BaS, CdS, and Ga₂S₃ at high temperatures. Single-crystal X-ray diffraction analysis revealed that it adopts a new orthorhombic structure type (space group Pccn, Z = 4, a = 12.7664(7) Å, b = 12.8060(7) Å, c = 12.1265(7) Å) consisting of one-dimensional anionic chains [CdGaS₅]^5– built from edge- and corner-sharing tetrahedra centred by Cd and Ga atoms in an ordered fashion, with Ba²⁺ cations located between the chains. The UV–vis–NIR diffuse reflectance spectrum reveals two optical transitions at 1.92(2) and 3.29(2) eV, the latter being consistent with the yellow colour of the crystals.