Materials Data on Nb5PbSe8 by Materials Project
Nb5PbSe8 is Orthorhombic Perovskite-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Nb+2.80+ sites. In the first Nb+2.80+ site, Nb+2.80+ is bonded to six Se2- atoms to form a mixture of corner and edge-sharing NbSe6 octahedra. The corner-sharing octahedral tilt angles are 49°. There are two shorter (2.66 Å) and four longer (2.67 Å) Nb–Se bond lengths. In the second Nb+2.80+ site, Nb+2.80+ is bonded to six Se2- atoms to form a mixture of distorted corner, edge, and face-sharing NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 50–53°. There are a spread of Nb–Se bond distances ranging from 2.55–2.93 Å. In the third Nb+2.80+ site, Nb+2.80+ is bonded to six Se2- atoms to form a mixture of corner, edge, and face-sharing NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 49–53°. There are a spread of Nb–Se bond distances ranging from 2.57–2.76 Å. Pb2+ is bonded in a distorted q6 geometry to ten Se2- atoms. There are a spread of Pb–Se bond distances ranging from 3.27–3.44 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 4-coordinate geometry to four Nb+2.80+ and one Pb2+ atom. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to three Nb+2.80+ and two equivalent Pb2+ atoms. In the third Se2- site, Se2- is bonded in a 3-coordinate geometry to three equivalent Nb+2.80+ and two equivalent Pb2+ atoms. In the fourth Se2- site, Se2- is bonded in a 5-coordinate geometry to five Nb+2.80+ atoms.