Materials Data on CaNi2(PO5)2 by Materials Project
CaNi2(PO5)2 crystallizes in the orthorhombic Fdd2 space group. The structure is three-dimensional. Ca2+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are two shorter (2.49 Å) and six longer (2.50 Å) Ca–O bond lengths. Ni4+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with two equivalent NiO6 octahedra and corners with four equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 69°. There are a spread of Ni–O bond distances ranging from 2.00–2.21 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four equivalent NiO6 octahedra. The corner-sharing octahedra tilt angles range from 44–57°. All P–O bond lengths are 1.55 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ni4+, and one P5+ atom. In the second O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Ni4+ and one O2- atom. The O–O bond length is 1.28 Å. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ni4+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ni4+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ni4+, and one P5+ atom.