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DOE OSTI · 1287845

Materials Data on KLi2AlSi4(O5F)2 by Materials Project

Abstract

KLi2AlSi4(O5F)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.53–3.01 Å. In the second K1+ site, K1+ is bonded to four O2- and two equivalent F1- atoms to form distorted KO4F2 octahedra that share corners with two equivalent SiO5F octahedra and edges with two equivalent SiO5F octahedra. The corner-sharing octahedral tilt angles are 20°. There are two shorter (2.22 Å) and two longer (2.59 Å) K–O bond lengths. Both K–F bond lengths are 2.55 Å. In the third K1+ site, K1+ is bonded in a 4-coordinate geometry to three O2- and one F1- atom. There are a spread of K–O bond distances ranging from 2.59–2.82 Å. The K–F bond length is 2.62 Å. There are five inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a distorted rectangular see-saw-like geometry to three O2- and one F1- atom. There are a spread of Li–O bond distances ranging from 1.95–1.99 Å. The Li–F bond length is 1.94 Å. In the second Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.87–2.29 Å. In the third Li1+ site, Li1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 1.97–2.47 Å. In the fourth Li1+ site, Li1+ is bonded in a distorted trigonal planar geometry to one O2- and two F1- atoms. The Li–O bond length is 1.85 Å. There is one shorter (1.88 Å) and one longer (2.02 Å) Li–F bond length. In the fifth Li1+ site, Li1+ is bonded in a 3-coordinate geometry to three O2- atoms. There is two shorter (1.84 Å) and one longer (1.95 Å) Li–O bond length. There are three inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded in a distorted T-shaped geometry to two O2- and one F1- atom. There is one shorter (1.90 Å) and one longer (1.95 Å) Al–O bond length. The Al–F bond length is 1.72 Å. In the second Al3+ site, Al3+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is one shorter (1.77 Å) and two longer (1.84 Å) Al–O bond length. In the third Al3+ site, Al3+ is bonded in a distorted square co-planar geometry to two equivalent O2- and two equivalent F1- atoms. Both Al–O bond lengths are 1.71 Å. Both Al–F bond lengths are 2.24 Å. There are ten inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Si–O bond distances ranging from 1.59–1.72 Å. In the second Si4+ site, Si4+ is bonded to five O2- atoms to form SiO5 trigonal bipyramids that share a cornercorner with one SiO4F2 octahedra and an edgeedge with one SiO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 68°. There are a spread of Si–O bond distances ranging from 1.70–1.82 Å. In the third Si4+ site, Si4+ is bonded to five O2- atoms to form distorted edge-sharing SiO5 trigonal bipyramids. There are a spread of Si–O bond distances ranging from 1.67–1.77 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form distorted SiO4 tetrahedra that share a cornercorner with one SiO4F2 octahedra and a cornercorner with one SiO3F tetrahedra. The corner-sharing octahedral tilt angles are 40°. There are a spread of Si–O bond distances ranging from 1.66–2.01 Å. In the fifth Si4+ site, Si4+ is bonded to three O2- and one F1- atom to form distorted corner-sharing SiO3F tetrahedra. There are a spread of Si–O bond distances ranging from 1.65–1.93 Å. The Si–F bond length is 1.72 Å. In the sixth Si4+ site, Si4+ is bonded to four O2- and two F1- atoms to form SiO4F2 octahedra that share a cornercorner with one SiO4 tetrahedra and a cornercorner with one SiO5 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.74–2.02 Å. There is one shorter (1.69 Å) and one longer (1.70 Å) Si–F bond length. In the seventh Si4+ site, Si4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Si–O bond distances ranging from 1.67–1.71 Å. In the eighth Si4+ site, Si4+ is bonded to five O2- and one F1- atom to form distorted SiO5F octahedra that share a cornercorner with one KO4F2 octahedra, an edgeedge with one KO4F2 octahedra, and an edgeedge with one SiO5F octahedra. The corner-sharing octahedral tilt angles are 20°. There are a spread of Si–O bond distances ranging from 1.76–2.03 Å. The Si–F bond length is 1.77 Å. In the ninth Si4+ site, Si4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Si–O bond distances ranging from 1.63–1.72 Å. In the tenth Si4+ site, Si4+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Si–O bond distances ranging from 1.64–1.74 Å. There are twenty-five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one K1+ and one Si4+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+ and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Al3+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Li1+ and two Si4+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two Si4+ and one O2- atom. The O–O bond length is 1.50 Å. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+ and two Si4+ atoms. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Li1+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Li1+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to one K1+ and two Si4+ atoms. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to one Al3+ and two Si4+ atoms. In the thirteenth O2- site, O2- is bonded in a T-shaped geometry to one Li1+ and two Si4+ atoms. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to one K1+, one Li1+, and two equivalent Si4+ atoms. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Li1+, one Al3+, and one O2- atom. In the sixteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Li1+ and one Si4+ atom. In the seventeenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Li1+ and two Si4+ atoms. In the eighteenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Al3+, and one Si4+ atom. In the nineteenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Si4+ atoms. In the twentieth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one K1+, one Li1+, and two equivalent Si4+ atoms. In the twenty-first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Al3+ and two Si4+ atoms. In the twenty-second O2- site, O2- is bonded in a bent 120 degrees geometry to two Si4+ atoms. In the twenty-third O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+ and one Si4+ atom. In the twenty-fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+ and two Si4+ atoms. In the twenty-fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Al3+ and one Si4+ atom. There are five inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to one K1+ and one Si4+ atom. In the second F1- site, F1- is bonded in a bent 150 degrees geometry to one Li1+ and one Al3+ atom. In the third F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Li1+ and one Si4+ atom. In the fourth F1- site, F1- is bonded in a 2-coordinate geometry to one K1+, one Li1+, and one Si4+ atom. In the fifth F1- site, F1- is bonded in a 1-coordinate geometry to one Al3+ and one Si4+ atom.

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2020-04-29. Materials Data on KLi2AlSi4(O5F)2 by Materials Project. https://doi.org/10.17188/1287845

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