Materials Data on Sr2LaI7 by Materials Project
Sr2LaI7 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are four inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six I1- atoms. There are a spread of Sr–I bond distances ranging from 3.30–3.84 Å. In the second Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven I1- atoms. There are a spread of Sr–I bond distances ranging from 3.32–3.63 Å. In the third Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven I1- atoms. There are a spread of Sr–I bond distances ranging from 3.33–3.57 Å. In the fourth Sr2+ site, Sr2+ is bonded to six I1- atoms to form distorted SrI6 pentagonal pyramids that share corners with two LaI6 octahedra and a faceface with one LaI6 octahedra. The corner-sharing octahedra tilt angles range from 56–59°. There are a spread of Sr–I bond distances ranging from 3.23–3.59 Å. There are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded to six I1- atoms to form LaI6 octahedra that share a cornercorner with one SrI6 pentagonal pyramid and a faceface with one SrI6 pentagonal pyramid. There are a spread of La–I bond distances ranging from 3.12–3.24 Å. In the second La3+ site, La3+ is bonded to six I1- atoms to form LaI6 octahedra that share a cornercorner with one SrI6 pentagonal pyramid. There are a spread of La–I bond distances ranging from 3.10–3.26 Å. There are fourteen inequivalent I1- sites. In the first I1- site, I1- is bonded in a water-like geometry to one Sr2+ and one La3+ atom. In the second I1- site, I1- is bonded in a distorted L-shaped geometry to one Sr2+ and one La3+ atom. In the third I1- site, I1- is bonded in a 3-coordinate geometry to two Sr2+ and one La3+ atom. In the fourth I1- site, I1- is bonded in a distorted trigonal planar geometry to two Sr2+ and one La3+ atom. In the fifth I1- site, I1- is bonded in a bent 120 degrees geometry to one Sr2+ and one La3+ atom. In the sixth I1- site, I1- is bonded in a distorted trigonal non-coplanar geometry to two Sr2+ and one La3+ atom. In the seventh I1- site, I1- is bonded in a 3-coordinate geometry to two Sr2+ and one La3+ atom. In the eighth I1- site, I1- is bonded in a distorted trigonal non-coplanar geometry to two Sr2+ and one La3+ atom. In the ninth I1- site, I1- is bonded in a distorted trigonal non-coplanar geometry to three Sr2+ atoms. In the tenth I1- site, I1- is bonded in a T-shaped geometry to three Sr2+ atoms. In the eleventh I1- site, I1- is bonded in a 3-coordinate geometry to two Sr2+ and one La3+ atom. In the twelfth I1- site, I1- is bonded in a bent 120 degrees geometry to one Sr2+ and one La3+ atom. In the thirteenth I1- site, I1- is bonded in a 3-coordinate geometry to two Sr2+ and one La3+ atom. In the fourteenth I1- site, I1- is bonded in a 3-coordinate geometry to two Sr2+ and one La3+ atom.