Materials Data on K2LaP2Se7 by Materials Project
K2LaP2Se7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 10-coordinate geometry to six Se2- atoms. There are a spread of K–Se bond distances ranging from 3.36–3.72 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 3.34–3.81 Å. La2+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of La–Se bond distances ranging from 3.06–3.26 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded in a tetrahedral geometry to four Se2- atoms. There are a spread of P–Se bond distances ranging from 2.22–2.25 Å. In the second P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se2- atoms. There are one shorter (2.20 Å) and two longer (2.21 Å) P–Se bond lengths. There are seven inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted see-saw-like geometry to two equivalent K1+, one La2+, and one P5+ atom. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to two K1+, one La2+, and one P5+ atom. In the third Se2- site, Se2- is bonded in a 1-coordinate geometry to three K1+, one La2+, and one P5+ atom. In the fourth Se2- site, Se2- is bonded in a 4-coordinate geometry to two K1+, one La2+, and one P5+ atom. In the fifth Se2- site, Se2- is bonded in a 1-coordinate geometry to two K1+, one La2+, and one P5+ atom. In the sixth Se2- site, Se2- is bonded in a 4-coordinate geometry to two K1+, one La2+, and one P5+ atom. In the seventh Se2- site, Se2- is bonded in a 4-coordinate geometry to one K1+, two equivalent La2+, and one P5+ atom.