DOI: 10.17188/1699580
title: Materials Data on Mg7P6(HO6)4 by Materials Project

description: Mg7P6(HO6)4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO6 octahedra, corners with six PO4 tetrahedra, an edgeedge with one MgO6 octahedra, and an edgeedge with one MgO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 63°. There are a spread of Mg–O bond distances ranging from 2.05–2.21 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with six PO4 tetrahedra, and corners with two equivalent MgO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 63°. There are a spread of Mg–O bond distances ranging from 2.07–2.28 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six PO4 tetrahedra, an edgeedge with one MgO6 octahedra, and an edgeedge with one MgO5 trigonal bipyramid. There are a spread of Mg–O bond distances ranging from 2.06–2.12 Å. In the fourth Mg2+ site, Mg2+ is bonded to five O2- atoms to form MgO5 trigonal bipyramids that share a cornercorner with one MgO6 octahedra, corners with five PO4 tetrahedra, and edges with two MgO6 octahedra. The corner-sharing octahedral tilt angles are 68°. There are a spread of Mg–O bond distances ranging from 2.02–2.15 Å. There are three inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with five MgO6 octahedra and corners with two equivalent MgO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 40–61°. There are a spread of P–O bond distances ranging from 1.54–1.60 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with six MgO6 octahedra and a cornercorner with one MgO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 25–55°. There are a spread of P–O bond distances ranging from 1.54–1.56 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four MgO6 octahedra and corners with two equivalent MgO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 31–59°. There are a spread of P–O bond distances ranging from 1.52–1.62 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.07 Å) and one longer (1.41 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.02 Å) and one longer (1.68 Å) H–O bond length. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one P5+ atom. In the second O2- site, O2- is bonded in a trigonal planar geometry to two Mg2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one P5+, and one H1+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Mg2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Mg2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted T-shaped geometry to one Mg2+, one P5+, and one H1+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one P5+, and one H1+ atom. In the eleventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a 1-coordinate geometry to one Mg2+, one P5+, and one H1+ atom.