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DOE OSTI · 1720525

Materials Data on NaMg2Al6VSi6B3H3O31 by Materials Project

Abstract

NaMg2VAl6B3Si6H3O31 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. Na1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Na–O bond distances ranging from 2.49–2.85 Å. Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two SiO4 tetrahedra, an edgeedge with one MgO6 octahedra, an edgeedge with one VO6 octahedra, and edges with two AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.03–2.20 Å. V3+ is bonded to six O2- atoms to form VO6 octahedra that share corners with two equivalent SiO4 tetrahedra, edges with two equivalent MgO6 octahedra, and edges with two equivalent AlO6 octahedra. There are a spread of V–O bond distances ranging from 1.88–2.22 Å. There are three inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO6 octahedra, corners with three SiO4 tetrahedra, an edgeedge with one VO6 octahedra, and edges with two AlO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Al–O bond distances ranging from 1.89–2.03 Å. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO6 octahedra, corners with three SiO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with two AlO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Al–O bond distances ranging from 1.86–2.00 Å. In the third Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one AlO6 octahedra, corners with three SiO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with two AlO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Al–O bond distances ranging from 1.86–1.99 Å. There are two inequivalent B3+ sites. In the first B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.37–1.40 Å. In the second B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.35 Å) and two longer (1.40 Å) B–O bond length. There are three inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one VO6 octahedra, corners with three AlO6 octahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–61°. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one MgO6 octahedra, corners with three AlO6 octahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–61°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one MgO6 octahedra, corners with three AlO6 octahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–61°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one B3+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one B3+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one B3+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Mg2+, one V3+, and one B3+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two equivalent Mg2+, and one B3+ atom. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+ and two equivalent Si4+ atoms. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+ and two Si4+ atoms. In the eleventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+ and two Si4+ atoms. In the twelfth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+ and two equivalent Si4+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted T-shaped geometry to two equivalent Mg2+ and one V3+ atom. In the fourteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one V3+, one Al3+, and one Si4+ atom. In the fifteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+, one Al3+, and one Si4+ atom. In the sixteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+, one Al3+, and one Si4+ atom. In the seventeenth O2- site, O2- is bonded in a distorted single-bond geometry to one V3+, two equivalent Al3+, and one H1+ atom. In the eighteenth O2- site, O2- is bonded in a distorted single-bond geometry to one Mg2+, two Al3+, and one H1+ atom.

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2020-05-01. Materials Data on NaMg2Al6VSi6B3H3O31 by Materials Project. https://doi.org/10.17188/1720525

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