Materials Data on SnI2 by Materials Project
SnI2 crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of one SnI2 sheet oriented in the (2, 0, 1) direction. there are two inequivalent Sn2+ sites. In the first Sn2+ site, Sn2+ is bonded to six I1- atoms to form SnI6 octahedra that share corners with four equivalent SnI5 square pyramids and edges with two equivalent SnI6 octahedra. There are four shorter (3.19 Å) and two longer (3.26 Å) Sn–I bond lengths. In the second Sn2+ site, Sn2+ is bonded to five I1- atoms to form SnI5 square pyramids that share corners with two equivalent SnI6 octahedra and edges with four equivalent SnI5 square pyramids. The corner-sharing octahedral tilt angles are 64°. There are a spread of Sn–I bond distances ranging from 3.04–3.27 Å. There are three inequivalent I1- sites. In the first I1- site, I1- is bonded in a trigonal non-coplanar geometry to three Sn2+ atoms. In the second I1- site, I1- is bonded in a 3-coordinate geometry to three equivalent Sn2+ atoms. In the third I1- site, I1- is bonded in an L-shaped geometry to two equivalent Sn2+ atoms.