Re‐investigation of Barium‐Gold(I)‐Tetra‐Thiostannate(IV), Ba[Au$_2$SnS$_4$], with Short Au$^{\mathrm I}$···Au$^{\mathrm I}$ Separation Showing Luminescence Properties

New investigations combining single crystal‐ and synchrotron‐based powder X‐ray diffraction data revealed that Ba[Au$_2$SnS$_4$] crystallizes in the orthorhombic crystal system in space group C222$_1$ instead of P2$_1$2$_1$2 as reported earlier. While the principle crystal structure is not altered, there are significant differences of the interatomic distances Au‐S and Sn‐S. A salient property of this crystal structure is the partial framework composed of AuS$_2$ dumbbells and SnS$_4$ tetrahedra to form chains [(Au$_2$SnS$_4$)$^{2–}$]∞ propagating in the [100] direction. Within the chains a short Au···Au separation of 2.9538(13) Å is observed, while the interchain Au···Au separation is longer at 3.383 Å. The Ba$^{2+}$ cation is eightfold coordinated by S$^{2–}$ anions in a distorted bicapped trigonal prismatic environment BaS$_8$. These polyhedra share all S$^{2–}$ anions thus generating a three‐dimensional network. This connection Scheme generates voids along [100] hosting [(Au$_2$SnS$_4$)$^{2–}$]∞ chains. In addition, the compound has been shown to be luminescent at the blue‐green spectral range with emission maximum at approximately 21000 cm$^{–1}$