DOE OSTI2020
CePt5Sb crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are two inequivalent Ce3+ sites. In the first Ce3+ site, Ce3+ is bonded to twelve Pt+1.20- atoms to form CePt12 cuboctahedra that share edges with six equivalent CePt12 cuboctahedra, edges with ten PtCe3Sb2Pt7 cuboctahedra, and faces with five PtCe3Sb2Pt7 cuboctahedra. There are a spread of Ce–Pt bond distances ranging from 3.13–3.30 Å. In the second Ce3+ site, Ce3+ is bonded in a distorted hexagonal planar geometry to eighteen Pt+1.20- atoms. There are a spread of Ce–Pt bond distances ranging from 3.08–3.63 Å. There are eight inequivalent Pt+1.20- sites. In the first Pt+1.20- site, Pt+1.20- is bonded to three Ce3+, seven Pt+1.20-, and two equivalent Sb3+ atoms to form distorted PtCe3Sb2Pt7 cuboctahedra that share corners with thirteen PtCe3Sb2Pt7 cuboctahedra, edges with two equivalent CePt12 cuboctahedra, edges with six PtCe3Sb2Pt7 cuboctahedra, a faceface with one CePt12 cuboctahedra, and faces with five PtCe3Sb2Pt7 cuboctahedra. There are a spread of Pt–Pt bond distances ranging from 2.69–2.83 Å. Both Pt–Sb bond lengths are 2.85 Å. In the second Pt+1.20- site, Pt+1.20- is bonded to three Ce3+, seven Pt+1.20-, and two equivalent Sb3+ atoms to form distorted PtCe3Sb2Pt7 cuboctahedra that share corners with ten PtCe3Sb2Pt7 cuboctahedra, edges with two equivalent CePt12 cuboctahedra, edges with four PtCe3Sb2Pt7 cuboctahedra, a faceface with one CePt12 cuboctahedra, and faces with nine PtCe3Sb2Pt7 cuboctahedra. There are a spread of Pt–Pt bond distances ranging from 2.68–2.86 Å. Both Pt–Sb bond lengths are 2.84 Å. In the third Pt+1.20- site, Pt+1.20- is bonded in a 12-coordinate geometry to three Ce3+, seven Pt+1.20-, and two equivalent Sb3+ atoms. There are two shorter (2.80 Å) and one longer (2.89 Å) Pt–Pt bond lengths. Both Pt–Sb bond lengths are 2.83 Å. In the fourth Pt+1.20- site, Pt+1.20- is bonded to three Ce3+, seven Pt+1.20-, and two equivalent Sb3+ atoms to form distorted PtCe3Sb2Pt7 cuboctahedra that share corners with ten PtCe3Sb2Pt7 cuboctahedra, edges with two equivalent CePt12 cuboctahedra, edges with six PtCe3Sb2Pt7 cuboctahedra, a faceface with one CePt12 cuboctahedra, and faces with eight equivalent PtCe3Sb2Pt7 cuboctahedra. There are two shorter (2.80 Å) and one longer (2.84 Å) Pt–Pt bond lengths. Both Pt–Sb bond lengths are 2.84 Å. In the fifth Pt+1.20- site, Pt+1.20- is bonded in a 4-coordinate geometry to three equivalent Ce3+, three Pt+1.20-, and one Sb3+ atom. The Pt–Sb bond length is 2.54 Å. In the sixth Pt+1.20- site, Pt+1.20- is bonded in a 4-coordinate geometry to three equivalent Ce3+, three Pt+1.20-, and one Sb3+ atom. The Pt–Sb bond length is 2.54 Å. In the seventh Pt+1.20- site, Pt+1.20- is bonded in a 3-coordinate geometry to three equivalent Ce3+ and six Pt+1.20- atoms. In the eighth Pt+1.20- site, Pt+1.20- is bonded in a 3-coordinate geometry to three equivalent Ce3+ and six Pt+1.20- atoms. There are two inequivalent Sb3+ sites. In the first Sb3+ site, Sb3+ is bonded in a 1-coordinate geometry to seven Pt+1.20- atoms. In the second Sb3+ site, Sb3+ is bonded in a 1-coordinate geometry to seven Pt+1.20- atoms.