DOI: 10.17188/1700328
title: Materials Data on Na4Mn2P2O7F6 by Materials Project

description: Na4Mn2P2O7F6 crystallizes in the monoclinic P2/c space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to two equivalent O2- and four F1- atoms to form distorted NaO2F4 octahedra that share corners with two equivalent MnO4F2 octahedra, corners with two equivalent PO4 tetrahedra, edges with two equivalent NaF6 octahedra, and edges with two equivalent MnO2F4 octahedra. The corner-sharing octahedral tilt angles are 71°. Both Na–O bond lengths are 2.42 Å. There are two shorter (2.38 Å) and two longer (2.48 Å) Na–F bond lengths. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to two equivalent O2- and four F1- atoms. Both Na–O bond lengths are 2.54 Å. There are two shorter (2.35 Å) and two longer (2.36 Å) Na–F bond lengths. In the third Na1+ site, Na1+ is bonded in a 6-coordinate geometry to four O2- and two equivalent F1- atoms. There are two shorter (2.32 Å) and two longer (2.81 Å) Na–O bond lengths. Both Na–F bond lengths are 2.52 Å. In the fourth Na1+ site, Na1+ is bonded to six F1- atoms to form distorted NaF6 octahedra that share corners with six MnO2F4 octahedra and edges with two equivalent NaO2F4 octahedra. The corner-sharing octahedra tilt angles range from 22–43°. There are a spread of Na–F bond distances ranging from 2.33–2.46 Å. There are two inequivalent Mn3+ sites. In the first Mn3+ site, Mn3+ is bonded to two equivalent O2- and four F1- atoms to form MnO2F4 octahedra that share corners with four equivalent NaF6 octahedra, corners with two equivalent PO4 tetrahedra, and edges with two equivalent NaO2F4 octahedra. The corner-sharing octahedra tilt angles range from 22–43°. Both Mn–O bond lengths are 2.18 Å. There is two shorter (1.88 Å) and two longer (1.92 Å) Mn–F bond length. In the second Mn3+ site, Mn3+ is bonded to four O2- and two equivalent F1- atoms to form MnO4F2 octahedra that share corners with four NaO2F4 octahedra and corners with four equivalent PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 37–71°. There are two shorter (1.98 Å) and two longer (2.24 Å) Mn–O bond lengths. Both Mn–F bond lengths are 1.90 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one NaO2F4 octahedra, corners with three MnO2F4 octahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 46–70°. There are a spread of P–O bond distances ranging from 1.51–1.64 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Mn3+, and one P5+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent P5+ atoms. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+, one Mn3+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Mn3+, and one P5+ atom. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a 4-coordinate geometry to three Na1+ and one Mn3+ atom. In the second F1- site, F1- is bonded in a 4-coordinate geometry to three Na1+ and one Mn3+ atom. In the third F1- site, F1- is bonded in a distorted T-shaped geometry to two Na1+ and one Mn3+ atom.