DOI: 10.17188/1285698
title: Materials Data on Mn9(PO4)8 by Materials Project

description: Mn9(PO4)8 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are six inequivalent Mn+2.67+ sites. In the first Mn+2.67+ site, Mn+2.67+ is bonded to five O2- atoms to form MnO5 trigonal bipyramids that share corners with two equivalent MnO6 octahedra and corners with five PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 63–67°. There are a spread of Mn–O bond distances ranging from 1.98–2.25 Å. In the second Mn+2.67+ site, Mn+2.67+ is bonded to six O2- atoms to form distorted MnO6 octahedra that share a cornercorner with one MnO6 octahedra, corners with four PO4 tetrahedra, corners with two equivalent MnO5 trigonal bipyramids, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Mn–O bond distances ranging from 1.92–2.45 Å. In the third Mn+2.67+ site, Mn+2.67+ is bonded in a distorted square co-planar geometry to six O2- atoms. There are a spread of Mn–O bond distances ranging from 2.08–2.70 Å. In the fourth Mn+2.67+ site, Mn+2.67+ is bonded in a square co-planar geometry to four O2- atoms. All Mn–O bond lengths are 1.94 Å. In the fifth Mn+2.67+ site, Mn+2.67+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Mn–O bond distances ranging from 1.89–2.70 Å. In the sixth Mn+2.67+ site, Mn+2.67+ is bonded to six O2- atoms to form distorted MnO6 octahedra that share corners with two equivalent MnO6 octahedra, corners with two equivalent PO4 tetrahedra, and edges with two equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Mn–O bond distances ranging from 2.15–2.41 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one MnO6 octahedra, a cornercorner with one MnO5 trigonal bipyramid, and an edgeedge with one MnO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of P–O bond distances ranging from 1.50–1.59 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one MnO6 octahedra and a cornercorner with one MnO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 40°. There is one shorter (1.55 Å) and three longer (1.56 Å) P–O bond length. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent MnO6 octahedra and a cornercorner with one MnO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 43–50°. There are a spread of P–O bond distances ranging from 1.54–1.56 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one MnO6 octahedra, corners with two equivalent MnO5 trigonal bipyramids, and an edgeedge with one MnO6 octahedra. The corner-sharing octahedral tilt angles are 45°. There are a spread of P–O bond distances ranging from 1.53–1.58 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two Mn+2.67+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Mn+2.67+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mn+2.67+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Mn+2.67+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mn+2.67+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two Mn+2.67+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to two Mn+2.67+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Mn+2.67+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mn+2.67+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two Mn+2.67+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a bent 120 degrees geometry to one Mn+2.67+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to two Mn+2.67+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Mn+2.67+ and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Mn+2.67+ and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Mn+2.67+ and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a bent 120 degrees geometry to one Mn+2.67+ and one P5+ atom.