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DOE OSTI · 1279821

Materials Data on NaBePO4 by Materials Project

Abstract

NaBePO4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.33–2.70 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with four BeO4 tetrahedra, corners with six PO4 tetrahedra, and an edgeedge with one BeO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.36–2.70 Å. In the third Na1+ site, Na1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Na–O bond distances ranging from 2.54–2.85 Å. There are three inequivalent Be2+ sites. In the first Be2+ site, Be2+ is bonded to four O2- atoms to form BeO4 tetrahedra that share a cornercorner with one NaO6 octahedra and corners with four PO4 tetrahedra. The corner-sharing octahedral tilt angles are 69°. There are a spread of Be–O bond distances ranging from 1.63–1.65 Å. In the second Be2+ site, Be2+ is bonded to four O2- atoms to form BeO4 tetrahedra that share a cornercorner with one NaO6 octahedra, corners with four PO4 tetrahedra, and an edgeedge with one NaO6 octahedra. The corner-sharing octahedral tilt angles are 72°. There are a spread of Be–O bond distances ranging from 1.63–1.65 Å. In the third Be2+ site, Be2+ is bonded to four O2- atoms to form BeO4 tetrahedra that share corners with two equivalent NaO6 octahedra and corners with four PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 61–76°. There is three shorter (1.63 Å) and one longer (1.65 Å) Be–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 two equivalent NaO6 octahedra and corners with four BeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–58°. There is three shorter (1.55 Å) and one longer (1.56 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent NaO6 octahedra and corners with four BeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 65–77°. There is three shorter (1.55 Å) and one 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 NaO6 octahedra and corners with four BeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–81°. All P–O bond lengths are 1.55 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+, one Be2+, and one P5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+, one Be2+, and one P5+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+, one Be2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+, one Be2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+, one Be2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+, one Be2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal pyramidal geometry to two Na1+, one Be2+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Be2+, and one P5+ atom. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+, one Be2+, and one P5+ atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Na1+, one Be2+, and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Na1+, one Be2+, and one P5+ atom. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Na1+, one Be2+, and one P5+ atom.

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2020-04-30. Materials Data on NaBePO4 by Materials Project. https://doi.org/10.17188/1279821

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