Materials Data on K4GeO4 by Materials Project

Abstract

K4GeO4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.71–2.91 Å. In the second K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.62–3.10 Å. In the third 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 2.71–3.35 Å. In the fourth K1+ site, K1+ is bonded to four O2- atoms to form distorted KO4 tetrahedra that share corners with four equivalent GeO4 tetrahedra and an edgeedge with one KO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.61–2.67 Å. Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with four equivalent KO4 tetrahedra. There is three shorter (1.80 Å) and one longer (1.81 Å) Ge–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to five K1+ and one Ge4+ atom. In the second O2- site, O2- is bonded to five K1+ and one Ge4+ atom to form a mixture of distorted corner and edge-sharing OK5Ge octahedra. The corner-sharing octahedra tilt angles range from 44–46°. In the third O2- site, O2- is bonded in a 1-coordinate geometry to five K1+ and one Ge4+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to five K1+ and one Ge4+ atom.