Materials Data on Sm2PbSe4 by Materials Project
Sm2PbSe4 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. Sm3+ is bonded to eight equivalent Se2- atoms to form distorted SmSe8 hexagonal bipyramids that share corners with four equivalent SmSe8 hexagonal bipyramids, corners with four equivalent PbSe8 hexagonal bipyramids, edges with four equivalent SmSe8 hexagonal bipyramids, faces with four equivalent SmSe8 hexagonal bipyramids, and faces with four equivalent PbSe8 hexagonal bipyramids. There are a spread of Sm–Se bond distances ranging from 2.96–3.22 Å. Pb2+ is bonded to eight equivalent Se2- atoms to form distorted PbSe8 hexagonal bipyramids that share corners with eight equivalent SmSe8 hexagonal bipyramids, edges with four equivalent PbSe8 hexagonal bipyramids, and faces with eight equivalent SmSe8 hexagonal bipyramids. There are four shorter (3.07 Å) and four longer (3.26 Å) Pb–Se bond lengths. Se2- is bonded in a 6-coordinate geometry to four equivalent Sm3+ and two equivalent Pb2+ atoms.