Materials Data on PmSi3 by Materials Project
PmSi3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Pm is bonded to twelve Si atoms to form a mixture of distorted face and corner-sharing PmSi12 cuboctahedra. There are a spread of Pm–Si bond distances ranging from 3.09–3.12 Å. There are three inequivalent Si sites. In the first Si site, Si is bonded in a 10-coordinate geometry to four equivalent Pm and six Si atoms. There are two shorter (2.52 Å) and four longer (2.73 Å) Si–Si bond lengths. In the second Si site, Si is bonded in a 10-coordinate geometry to four equivalent Pm and six Si atoms. There are one shorter (2.52 Å) and two longer (2.73 Å) Si–Si bond lengths. In the third Si site, Si is bonded in a 10-coordinate geometry to four equivalent Pm and six Si atoms.