Materials Data on SrCo2(AsO4)2 by Materials Project
SrCo2(AsO4)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Sr2+ is bonded to six O2- atoms to form distorted SrO6 pentagonal pyramids that share corners with four equivalent AsO4 tetrahedra, an edgeedge with one CoO6 octahedra, and an edgeedge with one SrO6 pentagonal pyramid. There are a spread of Sr–O bond distances ranging from 2.42–2.70 Å. There are two inequivalent Co2+ sites. In the first Co2+ site, Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent AsO4 tetrahedra, an edgeedge with one CoO6 octahedra, and an edgeedge with one SrO6 pentagonal pyramid. There are a spread of Co–O bond distances ranging from 2.08–2.27 Å. In the second Co2+ site, Co2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Co–O bond distances ranging from 1.97–2.32 Å. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are a spread of As–O bond distances ranging from 1.78–1.86 Å. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent CoO6 octahedra and corners with four equivalent SrO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 57–66°. There are a spread of As–O bond distances ranging from 1.72–1.74 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Co2+ and one As5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two Co2+ and one O2- atom. The O–O bond length is 1.49 Å. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Co2+ and one As5+ atom. In the fourth O2- site, O2- is bonded in a distorted tetrahedral geometry to one Sr2+, two Co2+, and one As5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+, one Co2+, and one As5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+, one Co2+, and one As5+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to one Sr2+, one As5+, and one O2- atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Sr2+ and one As5+ atom.