Materials Data on Cs3Sm2N9 by Materials Project
Cs3Sm2N9 crystallizes in the trigonal R-3c space group. The structure is three-dimensional. Cs1+ is bonded to twelve N1- atoms to form distorted CsN12 cuboctahedra that share corners with six equivalent CsN12 cuboctahedra, corners with four equivalent SmN6 pentagonal pyramids, faces with eight equivalent CsN12 cuboctahedra, and faces with four equivalent SmN6 pentagonal pyramids. There are a spread of Cs–N bond distances ranging from 3.23–3.76 Å. Sm3+ is bonded to six N1- atoms to form distorted SmN6 pentagonal pyramids that share corners with six equivalent CsN12 cuboctahedra, faces with six equivalent CsN12 cuboctahedra, and a faceface with one SmN6 pentagonal pyramid. There are three shorter (2.38 Å) and three longer (2.40 Å) Sm–N bond lengths. There are two inequivalent N1- sites. In the first N1- site, N1- is bonded in a 1-coordinate geometry to four equivalent Cs1+ and one Sm3+ atom. In the second N1- site, N1- is bonded in a distorted L-shaped geometry to four equivalent Cs1+ and two equivalent Sm3+ atoms.