DOI: 10.17188/1743977
title: Materials Data on KMg3GaSi3(HO6)2 by Materials Project

description: KMg3GaSi3(HO6)2 crystallizes in the triclinic P1 space group. The structure is two-dimensional and consists of one KMg3GaSi3(HO6)2 sheet oriented in the (0, 0, 1) direction. K1+ is bonded in a 6-coordinate geometry to three O2- atoms. All K–O bond lengths are 2.69 Å. There are three inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one GaO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.01–2.20 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one GaO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.02–2.15 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one GaO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.02–2.19 Å. Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with three MgO6 octahedra and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 62–63°. There is one shorter (1.82 Å) and three longer (1.85 Å) Ga–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 corners with three MgO6 octahedra and corners with three equivalent GaO4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. There is three shorter (1.65 Å) and one longer (1.67 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–58°. There is one shorter (1.61 Å) and three longer (1.67 Å) Si–O bond length. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–57°. There is one shorter (1.61 Å) and three longer (1.67 Å) Si–O bond length. 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 0.97 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three Mg2+ and one H1+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three Mg2+ and one H1+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one K1+, one Ga3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Si4+ atoms. In the fifth O2- site, O2- is bonded in a tetrahedral geometry to three Mg2+ and one Ga3+ atom. In the sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom. In the eighth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to one K1+, one Ga3+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one K1+, one Ga3+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Si4+ atoms. In the twelfth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Si4+ atoms.