DOI: 10.17188/1266738
title: Materials Data on K2BeH4(SeO5)2 by Materials Project

description: K2BeH4(SeO5)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to seven O2- atoms to form distorted KO7 pentagonal bipyramids that share a cornercorner with one BeO4 tetrahedra, corners with five SeO4 tetrahedra, an edgeedge with one SeO4 tetrahedra, and faces with two equivalent KO7 pentagonal bipyramids. There are a spread of K–O bond distances ranging from 2.76–3.09 Å. In the second 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 2.69–3.16 Å. Be2+ is bonded to four O2- atoms to form BeO4 tetrahedra that share a cornercorner with one KO7 pentagonal bipyramid and corners with two SeO4 tetrahedra. There are a spread of Be–O bond distances ranging from 1.62–1.66 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.63 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.71 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.71 Å) H–O bond length. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.69 Å) H–O bond length. There are two inequivalent Se6+ sites. In the first Se6+ site, Se6+ is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with two equivalent KO7 pentagonal bipyramids and a cornercorner with one BeO4 tetrahedra. There are a spread of Se–O bond distances ranging from 1.65–1.72 Å. In the second Se6+ site, Se6+ is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with three equivalent KO7 pentagonal bipyramids, a cornercorner with one BeO4 tetrahedra, and an edgeedge with one KO7 pentagonal bipyramid. There are a spread of Se–O bond distances ranging from 1.65–1.70 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Be2+, and one Se6+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three K1+ and one Se6+ atom. In the third O2- site, O2- is bonded in a trigonal planar geometry to one Be2+ and two H1+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent K1+, one H1+, and one Se6+ atom. In the fifth O2- site, O2- is bonded in a trigonal planar geometry to one Be2+ and two H1+ atoms. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, two H1+, and one Se6+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+, one H1+, and one Se6+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+, one Be2+, and one Se6+ atom. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent K1+ and one Se6+ atom. In the tenth O2- site, O2- is bonded in a 1-coordinate geometry to three K1+ and one Se6+ atom.