DOI: 10.17188/1321162
title: Materials Data on CaSnO2 by Materials Project

description: CaSnO2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.47 Å. In the second Ca2+ site, Ca2+ is bonded to five O2- atoms to form distorted CaO5 trigonal bipyramids that share corners with two equivalent CaO6 octahedra, a cornercorner with one SnO5 trigonal bipyramid, an edgeedge with one SnO5 trigonal bipyramid, and edges with two equivalent CaO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 51–65°. There are a spread of Ca–O bond distances ranging from 2.29–2.46 Å. In the third Ca2+ site, Ca2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Ca–O bond distances ranging from 2.24–2.39 Å. In the fourth Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share a cornercorner with one SnO5 trigonal bipyramid, corners with two equivalent CaO5 trigonal bipyramids, edges with two equivalent CaO6 octahedra, and an edgeedge with one SnO5 trigonal bipyramid. There are a spread of Ca–O bond distances ranging from 2.31–2.64 Å. There are four inequivalent Sn2+ sites. In the first Sn2+ site, Sn2+ is bonded to five O2- atoms to form distorted SnO5 trigonal bipyramids that share a cornercorner with one CaO6 octahedra, a cornercorner with one CaO5 trigonal bipyramid, corners with two equivalent SnO5 trigonal bipyramids, an edgeedge with one CaO6 octahedra, and an edgeedge with one CaO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 71°. There are a spread of Sn–O bond distances ranging from 2.08–2.27 Å. In the second Sn2+ site, Sn2+ is bonded in an L-shaped geometry to two O2- atoms. There are one shorter (2.19 Å) and one longer (2.23 Å) Sn–O bond lengths. In the third Sn2+ site, Sn2+ is bonded in a water-like geometry to two O2- atoms. There are one shorter (2.18 Å) and one longer (2.20 Å) Sn–O bond lengths. In the fourth Sn2+ site, Sn2+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Sn–O bond distances ranging from 2.12–2.28 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+ and three Sn2+ atoms. In the second O2- site, O2- is bonded to two equivalent Ca2+ and two Sn2+ atoms to form OCa2Sn2 tetrahedra that share corners with two equivalent OCa4Sn square pyramids, corners with three OCa2Sn2 tetrahedra, corners with three OCa3Sn trigonal pyramids, an edgeedge with one OCa4Sn square pyramid, and an edgeedge with one OCa3Sn trigonal pyramid. In the third O2- site, O2- is bonded to three Ca2+ and one Sn2+ atom to form distorted OCa3Sn trigonal pyramids that share a cornercorner with one OCa4Sn square pyramid, corners with four OCa2Sn2 tetrahedra, corners with three OCa3Sn trigonal pyramids, and an edgeedge with one OCa4Sn square pyramid. In the fourth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+ and two equivalent Sn2+ atoms. In the fifth O2- site, O2- is bonded to three Ca2+ and one Sn2+ atom to form distorted OCa3Sn trigonal pyramids that share corners with two equivalent OCa4Sn square pyramids, corners with three OCa2Sn2 tetrahedra, corners with three OCa3Sn trigonal pyramids, and edges with two OCa2Sn2 tetrahedra. In the sixth O2- site, O2- is bonded to four Ca2+ and one Sn2+ atom to form distorted OCa4Sn square pyramids that share corners with two equivalent OCa2Sn2 tetrahedra, corners with three OCa3Sn trigonal pyramids, edges with two equivalent OCa4Sn square pyramids, an edgeedge with one OCa2Sn2 tetrahedra, and an edgeedge with one OCa3Sn trigonal pyramid. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Sn2+ atom. In the eighth O2- site, O2- is bonded to three Ca2+ and one Sn2+ atom to form OCa3Sn tetrahedra that share corners with three OCa2Sn2 tetrahedra, corners with four OCa3Sn trigonal pyramids, and an edgeedge with one OCa3Sn trigonal pyramid.