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DOE OSTI · 1285471

Materials Data on K2MgH8(SO6)2 by Materials Project

Abstract

K2MgH8(SO6)2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 10-coordinate geometry to two H1+ and eight O2- atoms. There are one shorter (2.88 Å) and one longer (3.00 Å) K–H bond lengths. There are a spread of K–O bond distances ranging from 2.71–3.17 Å. In the second K1+ site, K1+ is bonded in a 1-coordinate geometry to one H1+ and nine O2- atoms. The K–H bond length is 2.93 Å. There are a spread of K–O bond distances ranging from 2.80–3.23 Å. There are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent SO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.12 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent SO4 tetrahedra. There are four shorter (2.10 Å) and two longer (2.11 Å) Mg–O bond lengths. There are eight 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 1.00 Å. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.69 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one K1+ and two O2- atoms. There is one shorter (1.00 Å) and one longer (1.72 Å) H–O bond length. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to two K1+ and one O2- atom. The H–O bond length is 0.99 Å. There are two inequivalent S6+ sites. In the first S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one MgO6 octahedra. The corner-sharing octahedral tilt angles are 20°. There are a spread of S–O bond distances ranging from 1.47–1.51 Å. In the second S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one MgO6 octahedra. The corner-sharing octahedral tilt angles are 33°. There is two shorter (1.49 Å) and two longer (1.50 Å) S–O bond length. There are thirteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two K1+, one Mg2+, and one S6+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to two K1+ and one S6+ atom. In the third O2- site, O2- is bonded in a distorted water-like geometry to one K1+, one Mg2+, and two H1+ atoms. In the fourth O2- site, O2- is bonded in a distorted water-like geometry to one K1+, one Mg2+, and two H1+ atoms. In the fifth O2- site, O2- is bonded in a distorted water-like geometry to two equivalent K1+, one Mg2+, and two equivalent H1+ atoms. In the sixth O2- site, O2- is bonded in a distorted water-like geometry to two equivalent K1+, one Mg2+, and two equivalent H1+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Mg2+ and two H1+ atoms. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, two H1+, and one S6+ atom. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to one K1+ and one S6+ atom. In the tenth O2- site, O2- is bonded in a distorted single-bond geometry to one K1+ and one S6+ atom. In the eleventh O2- site, O2- is bonded in a 1-coordinate geometry to two K1+ and one S6+ atom. In the twelfth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two K1+, one Mg2+, and one S6+ atom. In the thirteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two K1+ and one S6+ atom.

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2020-05-29. Materials Data on K2MgH8(SO6)2 by Materials Project. https://doi.org/10.17188/1285471

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