Materials Data on Ba13Si6(Sn4As11)2 by Materials Project

Ba13Si6(Sn4As11)2 crystallizes in the tetragonal I-42m space group. The structure is three-dimensional. there are three inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to seven As3- atoms. There are a spread of Ba–As bond distances ranging from 3.27–3.64 Å. In the second Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to seven As3- atoms. There are a spread of Ba–As bond distances ranging from 3.45–3.98 Å. In the third Ba2+ site, Ba2+ is bonded to six As3- atoms to form BaAs6 octahedra that share corners with four equivalent SiAs4 tetrahedra. There are four shorter (3.53 Å) and two longer (3.89 Å) Ba–As bond lengths. Sn2+ is bonded in a distorted T-shaped geometry to three As3- atoms. There are two shorter (2.76 Å) and one longer (2.77 Å) Sn–As bond lengths. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four As3- atoms to form SiAs4 tetrahedra that share a cornercorner with one BaAs6 octahedra and corners with three equivalent SiAs4 tetrahedra. The corner-sharing octahedral tilt angles are 47°. All Si–As bond lengths are 2.38 Å. In the second Si4+ site, Si4+ is bonded in a tetrahedral geometry to four equivalent As3- atoms. All Si–As bond lengths are 2.40 Å. There are five inequivalent As3- sites. In the first As3- site, As3- is bonded to three Ba2+, two equivalent Sn2+, and one Si4+ atom to form a mixture of distorted corner and edge-sharing AsBa3SiSn2 octahedra. The corner-sharing octahedral tilt angles are 43°. In the second As3- site, As3- is bonded in a 6-coordinate geometry to four Ba2+ and two equivalent Sn2+ atoms. In the third As3- site, As3- is bonded in a 5-coordinate geometry to three Ba2+ and two equivalent Si4+ atoms. In the fourth As3- site, As3- is bonded in a 7-coordinate geometry to five Ba2+, one Sn2+, and one Si4+ atom. In the fifth As3- site, As3- is bonded to four Ba2+ and two equivalent Si4+ atoms to form a mixture of distorted corner and edge-sharing AsBa4Si2 octahedra. The corner-sharing octahedral tilt angles are 43°.