Materials Data on NaSm3GeS7 by Materials Project
NaSm3GeS7 crystallizes in the hexagonal P6_3 space group. The structure is three-dimensional. Na1+ is bonded to six equivalent S2- atoms to form face-sharing NaS6 octahedra. There are three shorter (2.72 Å) and three longer (2.76 Å) Na–S bond lengths. Sm3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Sm–S bond distances ranging from 2.86–3.26 Å. Ge4+ is bonded in a tetrahedral geometry to four S2- atoms. There are one shorter (2.21 Å) and three longer (2.25 Å) Ge–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted tetrahedral geometry to three equivalent Sm3+ and one Ge4+ atom. In the second S2- site, S2- is bonded in a 6-coordinate geometry to two equivalent Na1+ and four equivalent Sm3+ atoms. In the third S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Sm3+ and one Ge4+ atom.