Materials Data on Sm4Fe3Co(AsO)4 by Materials Project

Sm4Fe3Co(AsO)4 crystallizes in the tetragonal P-42m space group. The structure is three-dimensional. Sm3+ is bonded in a 4-coordinate geometry to four equivalent As3- and four O2- atoms. There are two shorter (3.33 Å) and two longer (3.38 Å) Sm–As bond lengths. All Sm–O bond lengths are 2.31 Å. There are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to four equivalent As3- atoms to form FeAs4 tetrahedra that share corners with four equivalent CoAs4 tetrahedra and edges with four equivalent FeAs4 tetrahedra. All Fe–As bond lengths are 2.59 Å. In the second Fe2+ site, Fe2+ is bonded to four equivalent As3- atoms to form FeAs4 tetrahedra that share corners with four equivalent FeAs4 tetrahedra, edges with two equivalent FeAs4 tetrahedra, and edges with two equivalent CoAs4 tetrahedra. All Fe–As bond lengths are 2.56 Å. Co2+ is bonded to four equivalent As3- atoms to form CoAs4 tetrahedra that share corners with four equivalent FeAs4 tetrahedra and edges with four equivalent FeAs4 tetrahedra. All Co–As bond lengths are 2.53 Å. As3- is bonded in a 8-coordinate geometry to four equivalent Sm3+, three Fe2+, and one Co2+ atom. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Sm3+ atoms to form a mixture of corner and edge-sharing OSm4 tetrahedra. In the second O2- site, O2- is bonded to four equivalent Sm3+ atoms to form a mixture of corner and edge-sharing OSm4 tetrahedra. In the third O2- site, O2- is bonded to four equivalent Sm3+ atoms to form a mixture of corner and edge-sharing OSm4 tetrahedra.