Materials Data on K4Eu(PSe4)2 by Materials Project
K4Eu(PSe4)2 crystallizes in the orthorhombic Ibam space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of K–Se bond distances ranging from 3.27–3.67 Å. In the second K1+ site, K1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of K–Se bond distances ranging from 3.46–4.05 Å. Eu2+ is bonded to eight Se2- atoms to form distorted EuSe8 hexagonal bipyramids that share edges with two equivalent EuSe8 hexagonal bipyramids and edges with four equivalent PSe4 tetrahedra. There are four shorter (3.24 Å) and four longer (3.29 Å) Eu–Se bond lengths. P5+ is bonded to four Se2- atoms to form PSe4 tetrahedra that share edges with two equivalent EuSe8 hexagonal bipyramids. There are a spread of P–Se bond distances ranging from 2.22–2.25 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to three K1+, two equivalent Eu2+, and one P5+ atom. In the second Se2- site, Se2- is bonded in a 6-coordinate geometry to five K1+ and one P5+ atom. In the third Se2- site, Se2- is bonded in a 1-coordinate geometry to four K1+, one Eu2+, and one P5+ atom.