Materials Data on K4PbO4 by Materials Project

Abstract

K4PbO4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to five O2- atoms to form distorted KO5 trigonal bipyramids that share corners with three equivalent KO5 square pyramids, corners with three equivalent PbO4 tetrahedra, corners with two equivalent KO4 trigonal pyramids, edges with three equivalent KO5 square pyramids, an edgeedge with one PbO4 tetrahedra, and edges with two equivalent KO5 trigonal bipyramids. There are a spread of K–O bond distances ranging from 2.65–2.88 Å. In the second K1+ site, K1+ is bonded to five O2- atoms to form KO5 square pyramids that share a cornercorner with one PbO4 tetrahedra, corners with three equivalent KO5 trigonal bipyramids, corners with two equivalent KO4 trigonal pyramids, edges with two equivalent KO5 square pyramids, edges with two equivalent PbO4 tetrahedra, and edges with three equivalent KO5 trigonal bipyramids. There are a spread of K–O bond distances ranging from 2.79–2.98 Å. In the third 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 2.74–3.30 Å. In the fourth K1+ site, K1+ is bonded to four O2- atoms to form distorted KO4 trigonal pyramids that share corners with two equivalent KO5 square pyramids, corners with four equivalent PbO4 tetrahedra, corners with two equivalent KO5 trigonal bipyramids, and edges with two equivalent KO4 trigonal pyramids. There are a spread of K–O bond distances ranging from 2.67–2.72 Å. Pb4+ is bonded to four O2- atoms to form PbO4 tetrahedra that share a cornercorner with one KO5 square pyramid, corners with three equivalent KO5 trigonal bipyramids, corners with four equivalent KO4 trigonal pyramids, edges with two equivalent KO5 square pyramids, and an edgeedge with one KO5 trigonal bipyramid. There are one shorter (2.10 Å) and three longer (2.12 Å) Pb–O bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to five K1+ and one Pb4+ atom to form a mixture of edge and corner-sharing OK5Pb octahedra. The corner-sharing octahedra tilt angles range from 15–18°. In the second O2- site, O2- is bonded to five K1+ and one Pb4+ atom to form a mixture of edge and corner-sharing OK5Pb octahedra. The corner-sharing octahedra tilt angles range from 8–28°. In the third O2- site, O2- is bonded to five K1+ and one Pb4+ atom to form a mixture of distorted edge and corner-sharing OK5Pb octahedra. The corner-sharing octahedra tilt angles range from 8–28°. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to four K1+ and one Pb4+ atom.