Materials Data on K2SnC4O9 by Materials Project
K2SnC4O9 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.65–3.28 Å. In the second K1+ site, K1+ is bonded to seven O2- atoms to form distorted edge-sharing KO7 pentagonal bipyramids. There are a spread of K–O bond distances ranging from 2.71–2.90 Å. Sn2+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of Sn–O bond distances ranging from 2.20–2.41 Å. There are four inequivalent C+3.50+ sites. In the first C+3.50+ site, C+3.50+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.24 Å) and one longer (1.29 Å) C–O bond length. In the second C+3.50+ site, C+3.50+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.25 Å) and one longer (1.29 Å) C–O bond length. In the third C+3.50+ site, C+3.50+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.25 Å) and one longer (1.29 Å) C–O bond length. In the fourth C+3.50+ site, C+3.50+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.25 Å) and one longer (1.29 Å) C–O bond length. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+ and one C+3.50+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one K1+, one Sn2+, and one C+3.50+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one K1+ and one C+3.50+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+, one Sn2+, and one C+3.50+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+ and one C+3.50+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, one Sn2+, and one C+3.50+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one K1+ and one C+3.50+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to one K1+, one Sn2+, and one C+3.50+ atom. In the ninth O2- site, O2- is bonded in a distorted L-shaped geometry to two K1+ atoms.