Materials Data on Ba3SiI2 by Materials Project

Abstract

Ba3I2Si is Caswellsilverite-like structured and crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to two equivalent Si4- and four I1- atoms to form a mixture of edge and corner-sharing BaSi2I4 octahedra. The corner-sharing octahedra tilt angles range from 6–12°. There are one shorter (3.27 Å) and one longer (3.29 Å) Ba–Si bond lengths. There are a spread of Ba–I bond distances ranging from 3.66–3.87 Å. In the second Ba2+ site, Ba2+ is bonded to two equivalent Si4- and four I1- atoms to form a mixture of edge and corner-sharing BaSi2I4 octahedra. The corner-sharing octahedra tilt angles range from 4–9°. Both Ba–Si bond lengths are 3.28 Å. There are two shorter (3.59 Å) and two longer (3.78 Å) Ba–I bond lengths. Si4- is bonded to six Ba2+ atoms to form SiBa6 octahedra that share corners with six IBa6 octahedra, edges with three equivalent SiBa6 octahedra, and edges with nine IBa6 octahedra. The corner-sharing octahedra tilt angles range from 9–12°. There are two inequivalent I1- sites. In the first I1- site, I1- is bonded to six Ba2+ atoms to form IBa6 octahedra that share corners with two equivalent SiBa6 octahedra, corners with four IBa6 octahedra, edges with five equivalent SiBa6 octahedra, and edges with seven IBa6 octahedra. The corner-sharing octahedra tilt angles range from 9–14°. In the second I1- site, I1- is bonded to six Ba2+ atoms to form IBa6 octahedra that share corners with two equivalent IBa6 octahedra, corners with four equivalent SiBa6 octahedra, edges with four equivalent SiBa6 octahedra, and edges with eight IBa6 octahedra. The corner-sharing octahedra tilt angles range from 11–12°.