Materials Data on K3Sm(AsS4)2 by Materials Project
K3Sm(AsS4)2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a distorted body-centered cubic geometry to eight S2- atoms. There are a spread of K–S bond distances ranging from 3.24–3.61 Å. In the second K1+ site, K1+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of K–S bond distances ranging from 3.27–3.56 Å. In the third K1+ site, K1+ is bonded in a distorted square co-planar geometry to eight S2- atoms. There are a spread of K–S bond distances ranging from 3.18–3.86 Å. Sm3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Sm–S bond distances ranging from 2.85–3.12 Å. As5+ is bonded in a tetrahedral geometry to four S2- atoms. There are one shorter (2.16 Å) and three longer (2.20 Å) As–S bond lengths. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded to four K1+ and one As5+ atom to form a mixture of distorted edge and corner-sharing SK4As square pyramids. In the second S2- site, S2- is bonded in a 5-coordinate geometry to three K1+, one Sm3+, and one As5+ atom. In the third S2- site, S2- is bonded in a 4-coordinate geometry to three K1+, one Sm3+, and one As5+ atom. In the fourth S2- site, S2- is bonded in a 1-coordinate geometry to two K1+, two equivalent Sm3+, and one As5+ atom.