Materials Data on K2Se2O5 by Materials Project
K2Se2O5 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of K–O bond distances ranging from 2.69–3.16 Å. In the second K1+ site, K1+ is bonded to seven O2- atoms to form a mixture of distorted edge and corner-sharing KO7 pentagonal bipyramids. There are a spread of K–O bond distances ranging from 2.75–3.04 Å. In the third K1+ site, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.80–3.07 Å. In the fourth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of K–O bond distances ranging from 2.74–3.10 Å. There are four inequivalent Se4+ sites. In the first Se4+ site, Se4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.68–1.89 Å. In the second Se4+ site, Se4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.68–1.92 Å. In the third Se4+ site, Se4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.68–1.90 Å. In the fourth Se4+ site, Se4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.68–1.90 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three K1+ and one Se4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two K1+ and two Se4+ atoms. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three K1+ and one Se4+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to three K1+ and one Se4+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to three K1+ and one Se4+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to three K1+ and one Se4+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two K1+ and two Se4+ atoms. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to four K1+ and one Se4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to three K1+ and one Se4+ atom. In the tenth O2- site, O2- is bonded in a 1-coordinate geometry to three K1+ and one Se4+ atom.