Materials Data on K2SnO2 by Materials Project
K2SnO2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to five O2- atoms to form distorted edge-sharing KO5 trigonal bipyramids. There are a spread of K–O bond distances ranging from 2.67–2.95 Å. In the second K1+ site, K1+ is bonded to five O2- atoms to form distorted edge-sharing KO5 trigonal bipyramids. There are a spread of K–O bond distances ranging from 2.72–2.84 Å. In the third K1+ site, K1+ is bonded in a see-saw-like geometry to four O2- atoms. There are a spread of K–O bond distances ranging from 2.72–2.86 Å. In the fourth K1+ site, K1+ is bonded in a 3-coordinate geometry to three O2- atoms. There are two shorter (2.72 Å) and one longer (2.77 Å) K–O bond lengths. There are two inequivalent Sn2+ sites. In the first 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 2.02–2.18 Å. In the second 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 2.04–2.15 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to five K1+ and one Sn2+ atom to form distorted OK5Sn octahedra that share corners with three equivalent OK5Sn octahedra, a cornercorner with one OK3Sn2 trigonal bipyramid, edges with seven OK5Sn octahedra, and an edgeedge with one OK3Sn2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 14–18°. In the second O2- site, O2- is bonded to four K1+ and two equivalent Sn2+ atoms to form distorted OK4Sn2 octahedra that share corners with three equivalent OK3Sn2 trigonal bipyramids and edges with eight OK5Sn octahedra. In the third O2- site, O2- is bonded to three K1+ and two equivalent Sn2+ atoms to form distorted OK3Sn2 trigonal bipyramids that share corners with four OK5Sn octahedra, edges with four OK5Sn octahedra, and an edgeedge with one OK3Sn2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 29–78°. In the fourth O2- site, O2- is bonded to five K1+ and one Sn2+ atom to form distorted OK5Sn octahedra that share corners with three equivalent OK5Sn octahedra, edges with four OK5Sn octahedra, and edges with three equivalent OK3Sn2 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 14–18°.