DOI: 10.17188/1731656
title: Materials Data on Ca4Mg4P4O17F3 by Materials Project

description: Ca4Mg4P4O17F3 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are three inequivalent Ca sites. In the first Ca site, Ca is bonded in a 5-coordinate geometry to seven O atoms. There are a spread of Ca–O bond distances ranging from 2.24–2.75 Å. In the second Ca site, Ca is bonded in a 7-coordinate geometry to six O and one F atom. There are a spread of Ca–O bond distances ranging from 2.42–2.73 Å. The Ca–F bond length is 2.24 Å. In the third Ca site, Ca is bonded in a 7-coordinate geometry to six O and one F atom. There are a spread of Ca–O bond distances ranging from 2.41–2.74 Å. The Ca–F bond length is 2.24 Å. There are two inequivalent Mg sites. In the first Mg site, Mg is bonded to four O and two F atoms to form MgO4F2 octahedra that share corners with two MgO4F2 octahedra and corners with four PO4 tetrahedra. The corner-sharing octahedral tilt angles are 45°. There are a spread of Mg–O bond distances ranging from 2.12–2.16 Å. There is one shorter (1.91 Å) and one longer (1.92 Å) Mg–F bond length. In the second Mg site, Mg is bonded to five O and one F atom to form MgO5F octahedra that share corners with two MgO4F2 octahedra and corners with four PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–46°. There are a spread of Mg–O bond distances ranging from 1.94–2.16 Å. The Mg–F bond length is 1.91 Å. There are three inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with four MgO4F2 octahedra. The corner-sharing octahedra tilt angles range from 39–53°. All P–O bond lengths are 1.56 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with four MgO4F2 octahedra. The corner-sharing octahedra tilt angles range from 38–53°. All P–O bond lengths are 1.56 Å. In the third P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with four MgO4F2 octahedra. The corner-sharing octahedra tilt angles range from 39–53°. All P–O bond lengths are 1.56 Å. There are nine inequivalent O sites. In the first O site, O is bonded in a 4-coordinate geometry to two Ca, one Mg, and one P atom. In the second O site, O is bonded in a 4-coordinate geometry to two Ca, one Mg, and one P atom. In the third O site, O is bonded in a 4-coordinate geometry to two Ca, one Mg, and one P atom. In the fourth O site, O is bonded in a 4-coordinate geometry to two Ca, one Mg, and one P atom. In the fifth O site, O is bonded in a trigonal planar geometry to one Ca and two equivalent Mg atoms. In the sixth O site, O is bonded in a 3-coordinate geometry to one Ca, one Mg, and one P atom. In the seventh O site, O is bonded in a 3-coordinate geometry to one Ca, one Mg, and one P atom. In the eighth O site, O is bonded in a 3-coordinate geometry to one Ca, one Mg, and one P atom. In the ninth O site, O is bonded in a 3-coordinate geometry to one Ca, one Mg, and one P atom. There are two inequivalent F sites. In the first F site, F is bonded in a trigonal planar geometry to one Ca and two equivalent Mg atoms. In the second F site, F is bonded in a trigonal planar geometry to one Ca and two Mg atoms.