Materials Data on K6Pb2O5 by Materials Project

Abstract

K6Pb2O5 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are six inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to five O2- atoms to form distorted KO5 square pyramids that share corners with two equivalent KO4 trigonal pyramids, an edgeedge with one KO5 square pyramid, and edges with two equivalent KO4 trigonal pyramids. There are a spread of K–O bond distances ranging from 2.70–3.09 Å. In the second K1+ site, K1+ is bonded to four O2- atoms to form distorted KO4 trigonal pyramids that share corners with two equivalent KO5 square pyramids, edges with two equivalent KO5 square pyramids, and an edgeedge with one KO4 trigonal pyramid. There are a spread of K–O bond distances ranging from 2.63–2.91 Å. In the third K1+ site, K1+ is bonded in a distorted see-saw-like geometry to four O2- atoms. There are a spread of K–O bond distances ranging from 2.68–2.77 Å. In the fourth K1+ site, K1+ is bonded in a see-saw-like geometry to four O2- atoms. There are a spread of K–O bond distances ranging from 2.67–2.85 Å. In the fifth K1+ site, K1+ is bonded in a see-saw-like geometry to four O2- atoms. There are a spread of K–O bond distances ranging from 2.70–2.83 Å. In the sixth K1+ site, K1+ is bonded in a T-shaped geometry to three O2- atoms. There are a spread of K–O bond distances ranging from 2.61–2.72 Å. There are two inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are two shorter (2.19 Å) and one longer (2.31 Å) Pb–O bond lengths. In the second Pb2+ site, Pb2+ is bonded in a 3-coordinate geometry to three O2- atoms. There are two shorter (2.18 Å) and one longer (2.31 Å) Pb–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to four K1+ and two Pb2+ atoms to form a mixture of distorted edge and corner-sharing OK4Pb2 octahedra. The corner-sharing octahedra tilt angles range from 12–14°. In the second O2- site, O2- is bonded to five K1+ and one Pb2+ atom to form OK5Pb octahedra that share corners with three equivalent OK5Pb octahedra and edges with seven OK4Pb2 octahedra. The corner-sharing octahedra tilt angles range from 8–13°. In the third O2- site, O2- is bonded to five K1+ and one Pb2+ atom to form distorted OK5Pb octahedra that share corners with four OK4Pb2 octahedra and edges with seven OK5Pb octahedra. The corner-sharing octahedra tilt angles range from 12–26°. In the fourth O2- site, O2- is bonded to five K1+ and one Pb2+ atom to form OK5Pb octahedra that share a cornercorner with one OK5Pb octahedra and edges with eight OK4Pb2 octahedra. The corner-sharing octahedral tilt angles are 18°. In the fifth O2- site, O2- is bonded to five K1+ and one Pb2+ atom to form OK5Pb octahedra that share corners with four OK5Pb octahedra and edges with seven OK4Pb2 octahedra. The corner-sharing octahedra tilt angles range from 8–26°.