Materials Data on K4Sb2O5 by Materials Project

Abstract

K4Sb2O5 crystallizes in the orthorhombic Amm2 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 one shorter (2.72 Å) and four longer (2.82 Å) K–O bond lengths. In the second K1+ site, K1+ is bonded in a 4-coordinate geometry to six O2- atoms. There are four shorter (2.82 Å) and two longer (3.36 Å) K–O bond lengths. In the third K1+ site, K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are two shorter (2.71 Å) and four longer (2.93 Å) K–O bond lengths. In the fourth K1+ site, K1+ is bonded to six O2- atoms to form distorted KO6 pentagonal pyramids that share corners with two equivalent SbO4 tetrahedra and edges with two equivalent KO6 pentagonal pyramids. There are two shorter (2.70 Å) and four longer (2.91 Å) K–O bond lengths. There are two inequivalent Sb3+ sites. In the first Sb3+ site, Sb3+ is bonded to four O2- atoms to form SbO4 tetrahedra that share corners with two equivalent KO6 pentagonal pyramids and corners with two equivalent SbO4 tetrahedra. There are two shorter (1.93 Å) and two longer (2.09 Å) Sb–O bond lengths. In the second Sb3+ site, Sb3+ is bonded in a water-like geometry to two equivalent O2- atoms. Both Sb–O bond lengths are 1.95 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to five K1+ and one Sb3+ atom to form a mixture of distorted edge, face, and corner-sharing OK5Sb octahedra. The corner-sharing octahedra tilt angles range from 42–65°. In the second O2- site, O2- is bonded to five K1+ and one Sb3+ atom to form a mixture of distorted edge, face, and corner-sharing OK5Sb octahedra. The corner-sharing octahedra tilt angles range from 42–65°. In the third O2- site, O2- is bonded in a 3-coordinate geometry to three K1+ and two equivalent Sb3+ atoms.