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DOE OSTI · 1757915

Materials Data on CaMg5P3HCO16 by Materials Project

Abstract

CaMg5CP3HO16 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.32–2.77 Å. There are five inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four PO4 tetrahedra, edges with two MgO6 octahedra, and an edgeedge with one MgO5 trigonal bipyramid. There are a spread of Mg–O bond distances ranging from 2.08–2.18 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with two PO4 tetrahedra, a cornercorner with one MgO5 trigonal bipyramid, edges with two MgO6 octahedra, and an edgeedge with one MgO6 pentagonal pyramid. There are a spread of Mg–O bond distances ranging from 2.00–2.37 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO6 pentagonal pyramid, corners with six PO4 tetrahedra, and edges with two MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.15 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 pentagonal pyramids that share a cornercorner with one MgO6 octahedra, corners with three PO4 tetrahedra, a cornercorner with one MgO5 trigonal bipyramid, an edgeedge with one MgO6 octahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 73°. There are a spread of Mg–O bond distances ranging from 2.07–2.19 Å. In the fifth Mg2+ site, Mg2+ is bonded to five O2- atoms to form MgO5 trigonal bipyramids that share a cornercorner with one MgO6 octahedra, a cornercorner with one MgO6 pentagonal pyramid, corners with four PO4 tetrahedra, an edgeedge with one MgO6 octahedra, and an edgeedge with one MgO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 56°. There are a spread of Mg–O bond distances ranging from 2.03–2.06 Å. C4+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.29 Å) and one longer (1.30 Å) C–O bond length. 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 four MgO6 octahedra, a cornercorner with one MgO6 pentagonal pyramid, and a cornercorner with one MgO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 46–57°. There are a spread of P–O bond distances ranging from 1.55–1.57 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four MgO6 octahedra, a cornercorner with one MgO6 pentagonal pyramid, and corners with three equivalent MgO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 39–57°. 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, a cornercorner with one MgO6 pentagonal pyramid, and an edgeedge with one MgO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 47–53°. There are a spread of P–O bond distances ranging from 1.54–1.58 Å. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Mg2+, and one P5+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Mg2+, and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Mg2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, two Mg2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+, one Mg2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Mg2+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a 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 equivalent Mg2+ and one C4+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Mg2+, and one P5+ 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 distorted trigonal planar geometry to two Mg2+ and one C4+ atom. In the thirteenth O2- site, O2- is bonded in a distorted single-bond geometry to three Mg2+ and one H1+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Mg2+, and one C4+ atom. In the fifteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Mg2+ and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one P5+ atom.

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2020-09-03. Materials Data on CaMg5P3HCO16 by Materials Project. https://doi.org/10.17188/1757915

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