Materials Data on Mg7P2(HO2)8 by Materials Project
Mg7P2(HO2)8 crystallizes in the monoclinic P2_1/c 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 corners with two equivalent MgO6 octahedra and corners with four equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of Mg–O bond distances ranging from 2.05–2.21 Å. In the second Mg2+ site, Mg2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Mg–O bond distances ranging from 2.05–2.15 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent PO4 tetrahedra and edges with five MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.02–2.21 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO6 octahedra, corners with two equivalent PO4 tetrahedra, and edges with three equivalent MgO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of Mg–O bond distances ranging from 2.04–2.27 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with six MgO6 octahedra. The corner-sharing octahedra tilt angles range from 38–60°. There are a spread of P–O bond distances ranging from 1.54–1.59 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three Mg2+ and one H1+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one P5+ atom. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to three Mg2+ and one H1+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to three Mg2+ and one H1+ atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to three Mg2+ and one H1+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mg2+ and one P5+ atom.