DOE OSTI2020
Sc5Pt9Si7 crystallizes in the hexagonal P-6 space group. The structure is three-dimensional. there are three inequivalent Sc+2.80+ sites. In the first Sc+2.80+ site, Sc+2.80+ is bonded in a 9-coordinate geometry to nine Pt2- atoms. There are six shorter (3.23 Å) and three longer (3.33 Å) Sc–Pt bond lengths. In the second Sc+2.80+ site, Sc+2.80+ is bonded in a 6-coordinate geometry to nine Pt2- atoms. There are six shorter (3.12 Å) and three longer (3.43 Å) Sc–Pt bond lengths. In the third Sc+2.80+ site, Sc+2.80+ is bonded in a 7-coordinate geometry to seven Pt2- atoms. There are a spread of Sc–Pt bond distances ranging from 2.92–3.04 Å. There are three inequivalent Pt2- sites. In the first Pt2- site, Pt2- is bonded in a 4-coordinate geometry to four Sc+2.80+, two equivalent Pt2-, and four Si+0.57+ atoms. Both Pt–Pt bond lengths are 2.87 Å. There are a spread of Pt–Si bond distances ranging from 2.36–2.48 Å. In the second Pt2- site, Pt2- is bonded in a 2-coordinate geometry to four Sc+2.80+, one Pt2-, and four Si+0.57+ atoms. The Pt–Pt bond length is 2.84 Å. There are a spread of Pt–Si bond distances ranging from 2.36–2.80 Å. In the third Pt2- site, Pt2- is bonded in a 12-coordinate geometry to five Sc+2.80+, three Pt2-, and four Si+0.57+ atoms. There are three shorter (2.48 Å) and one longer (2.53 Å) Pt–Si bond lengths. There are three inequivalent Si+0.57+ sites. In the first Si+0.57+ site, Si+0.57+ is bonded in a 6-coordinate geometry to six Pt2- atoms. In the second Si+0.57+ site, Si+0.57+ is bonded in a 5-coordinate geometry to five Pt2- atoms. In the third Si+0.57+ site, Si+0.57+ is bonded in a trigonal planar geometry to three equivalent Pt2- atoms.