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DOE OSTI · 1276481

Materials Data on KNa3Al4(GeO4)4 by Materials Project

Abstract

KNa3Al4(GeO4)4 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.74–3.25 Å. There are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.39–2.75 Å. In the second Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.52–2.97 Å. In the third Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.52–3.03 Å. There are four inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with three GeO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.74–1.79 Å. In the second Al3+ site, Al3+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.76 Å) and one longer (1.77 Å) Al–O bond length. In the third Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with three GeO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.75–1.77 Å. In the fourth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two GeO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.74–1.82 Å. There are four inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with three AlO4 tetrahedra. There is three shorter (1.76 Å) and one longer (1.77 Å) Ge–O bond length. In the second Ge4+ site, Ge4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. All Ge–O bond lengths are 1.82 Å. In the third Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with two AlO4 tetrahedra. There are a spread of Ge–O bond distances ranging from 1.75–1.82 Å. In the fourth Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with three AlO4 tetrahedra. There is three shorter (1.76 Å) and one longer (1.78 Å) Ge–O bond length. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one K1+, one Na1+, one Al3+, and one Ge4+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Na1+, one Al3+, and one Ge4+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Na1+, one Al3+, and one Ge4+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Na1+, one Al3+, and one Ge4+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+, one Al3+, and one O2- atom. The O–O bond length is 1.50 Å. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+, one Na1+, one Al3+, and one Ge4+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+, one Al3+, and one Ge4+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Al3+, and one Ge4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to one K1+, one Na1+, one Al3+, and one Ge4+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Al3+, and one Ge4+ atom. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Na1+, one Al3+, and one Ge4+ atom. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Na1+, one Al3+, and one Ge4+ atom. In the thirteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+, one Al3+, and one Ge4+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Ge4+, and one O2- atom. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Na1+, one Al3+, and one Ge4+ atom. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to one K1+, one Na1+, one Al3+, and one Ge4+ atom.

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2020-04-29. Materials Data on KNa3Al4(GeO4)4 by Materials Project. https://doi.org/10.17188/1276481

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36 MATERIALS SCIENCE↗