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DOE OSTI · 1757343

Materials Data on Na4Ga4Si19 by Materials Project

Abstract

NaNa7(Ga4Si19)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional and consists of one sodium molecule and one Na7(Ga4Si19)2 framework. In the Na7(Ga4Si19)2 framework, there are seven inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 8-coordinate geometry to seventeen Si+0.63- atoms. There are a spread of Na–Si bond distances ranging from 3.29–3.43 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six Si+0.63- atoms. There are a spread of Na–Si bond distances ranging from 3.50–3.54 Å. In the third Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six Si+0.63- atoms. There are a spread of Na–Si bond distances ranging from 3.49–3.52 Å. In the fourth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six Si+0.63- atoms. There are a spread of Na–Si bond distances ranging from 3.51–3.53 Å. In the fifth Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven Si+0.63- atoms. There are a spread of Na–Si bond distances ranging from 3.51–3.53 Å. In the sixth Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven Si+0.63- atoms. There are a spread of Na–Si bond distances ranging from 3.50–3.52 Å. In the seventh Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eighteen Si+0.63- atoms. There are a spread of Na–Si bond distances ranging from 3.30–3.42 Å. There are eight inequivalent Ga2+ sites. In the first Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share a cornercorner with one GaSi4 tetrahedra and corners with three SiNa3Si4 tetrahedra. There are a spread of Ga–Si bond distances ranging from 2.43–2.47 Å. In the second Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share corners with two GaSi4 tetrahedra and corners with two SiNa2Si4 tetrahedra. There are two shorter (2.44 Å) and two longer (2.47 Å) Ga–Si bond lengths. In the third Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share corners with two GaSi4 tetrahedra and corners with two SiNa3Si4 tetrahedra. There are a spread of Ga–Si bond distances ranging from 2.44–2.48 Å. In the fourth Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share corners with two GaSi4 tetrahedra and corners with five SiNa3Si4 tetrahedra. There are a spread of Ga–Si bond distances ranging from 2.44–2.47 Å. In the fifth Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share corners with three SiNa2Si4 tetrahedra and corners with four GaSi4 tetrahedra. There are three shorter (2.45 Å) and one longer (2.46 Å) Ga–Si bond lengths. In the sixth Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share corners with two SiNa3Si4 tetrahedra and corners with three GaSi4 tetrahedra. There are a spread of Ga–Si bond distances ranging from 2.44–2.47 Å. In the seventh Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share corners with two GaSi4 tetrahedra and corners with three SiNa3Si4 tetrahedra. There are a spread of Ga–Si bond distances ranging from 2.44–2.46 Å. In the eighth Ga2+ site, Ga2+ is bonded to four Si+0.63- atoms to form GaSi4 tetrahedra that share corners with two GaSi4 tetrahedra and corners with five SiNa2Si4 tetrahedra. There are two shorter (2.45 Å) and two longer (2.46 Å) Ga–Si bond lengths. There are thirty-eight inequivalent Si+0.63- sites. In the first Si+0.63- site, Si+0.63- is bonded in a tetrahedral geometry to one Ga2+ and three Si+0.63- atoms. There are two shorter (2.41 Å) and one longer (2.42 Å) Si–Si bond lengths. In the second Si+0.63- site, Si+0.63- is bonded in a tetrahedral geometry to two Ga2+ and two Si+0.63- atoms. Both Si–Si bond lengths are 2.40 Å. In the third Si+0.63- site, Si+0.63- is bonded in a tetrahedral geometry to two Ga2+ and two Si+0.63- atoms. There are one shorter (2.40 Å) and one longer (2.41 Å) Si–Si bond lengths. In the fourth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to one Na1+, one Ga2+, and three Si+0.63- atoms. There are a spread of Si–Si bond distances ranging from 2.35–2.39 Å. In the fifth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+, two Ga2+, and two Si+0.63- atoms. There are one shorter (2.35 Å) and one longer (2.36 Å) Si–Si bond lengths. In the sixth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. There are a spread of Si–Si bond distances ranging from 2.36–2.41 Å. In the seventh Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. There are a spread of Si–Si bond distances ranging from 2.38–2.40 Å. In the eighth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. There are one shorter (2.39 Å) and two longer (2.40 Å) Si–Si bond lengths. In the ninth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to one Na1+, one Ga2+, and three Si+0.63- atoms. There are one shorter (2.38 Å) and one longer (2.40 Å) Si–Si bond lengths. In the tenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+, one Ga2+, and three Si+0.63- atoms. There are one shorter (2.37 Å) and one longer (2.39 Å) Si–Si bond lengths. In the eleventh Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. There are two shorter (2.38 Å) and one longer (2.40 Å) Si–Si bond lengths. In the twelfth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+, one Ga2+, and three Si+0.63- atoms. There are one shorter (2.36 Å) and two longer (2.37 Å) Si–Si bond lengths. In the thirteenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. All Si–Si bond lengths are 2.39 Å. In the fourteenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. There are a spread of Si–Si bond distances ranging from 2.38–2.40 Å. In the fifteenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+, two Ga2+, and two Si+0.63- atoms. There are one shorter (2.33 Å) and one longer (2.36 Å) Si–Si bond lengths. In the sixteenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. There are a spread of Si–Si bond distances ranging from 2.37–2.40 Å. In the seventeenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+, one Ga2+, and three Si+0.63- atoms. Both Si–Si bond lengths are 2.38 Å. In the eighteenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+ and four Si+0.63- atoms. There are two shorter (2.38 Å) and one longer (2.39 Å) Si–Si bond lengths. In the nineteenth Si+0.63- site, Si+0.63- is bonded in a 5-coordinate geometry to one Na1+, one Ga2+, and three Si+0.63- atoms. There are one shorter (2.38 Å) and one longer (2.39 Å) Si–Si bond lengths. In the twentieth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, two Ga2+, and two Si+0.63- atoms. In the twenty-first Si+0.63- site, Si+0.63- is bonded to three Na1+ and four Si+0.63- atoms to form distorted SiNa3Si4 tetrahedra that share corners with two GaSi4 tetrahedra, corners with five SiNa2Si4 tetrahedra, and an edgeedge with one SiNa3Si4 tetrahedra. The Si–Si bond length is 2.43 Å. In the twenty-second Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, one Ga2+, and three Si+0.63- atoms. In the twenty-third Si+0.63- site, Si+0.63- is bonded to two Na1+ and four Si+0.63- atoms to form distorted SiNa2Si4 tetrahedra that share corners with four GaSi4 tetrahedra and corners with four SiNa3Si4 tetrahedra. The Si–Si bond length is 2.43 Å. In the twenty-fourth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to two Na1+, one Ga2+, and three Si+0.63- atoms. In the twenty-fifth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to two Na1+, two Ga2+, and two Si+0.63- atoms. In the twenty-sixth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, one Ga2+, and three Si+0.63- atoms. The Si–Si bond length is 2.43 Å. In the twenty-seventh Si+0.63- site, Si+0.63- is bonded to three Na1+ and four Si+0.63- atoms to form distorted SiNa3Si4 tetrahedra that share corners with five GaSi4 tetrahedra, corners with six SiNa2Si4 tetrahedra, and an edgeedge with one SiNa3Si4 tetrahedra. In the twenty-eighth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, two Ga2+, and two Si+0.63- atoms. In the twenty-ninth Si+0.63- site, Si+0.63- is bonded to two Na1+ and four Si+0.63- atoms to form distorted SiNa2Si4 tetrahedra that share corners with three SiNa2Si4 tetrahedra, corners with four GaSi4 tetrahedra, and edges with two SiNa3Si4 tetrahedra. The Si–Si bond length is 2.44 Å. In the thirtieth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to two Na1+, one Ga2+, and three Si+0.63- atoms. In the thirty-first Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to two Na1+, two Ga2+, and two Si+0.63- atoms. In the thirty-second Si+0.63- site, Si+0.63- is bonded to three Na1+ and four Si+0.63- atoms to form distorted SiNa3Si4 tetrahedra that share corners with three GaSi4 tetrahedra, corners with five SiNa3Si4 tetrahedra, and an edgeedge with one SiNa2Si4 tetrahedra. The Si–Si bond length is 2.43 Å. In the thirty-third Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, one Ga2+, and three Si+0.63- atoms. In the thirty-fourth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, two Ga2+, and two Si+0.63- atoms. In the thirty-fifth Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, one Ga2+, and three Si+0.63- atoms. The Si–Si bond length is 2.42 Å. In the thirty-sixth Si+0.63- site, Si+0.63- is bonded to three Na1+ and four Si+0.63- atoms to form distorted SiNa3Si4 tetrahedra that share corners with four GaSi4 tetrahedra, corners with five SiNa3Si4 tetrahedra, an edgeedge with one SiNa2Si4 tetrahedra, and a faceface with one SiNa3Si4 tetrahedra. In the thirty-seventh Si+0.63- site, Si+0.63- is bonded in a 4-coordinate geometry to three Na1+, one Ga2+, and three Si+0.63- atoms. The Si–Si bond length is 2.42 Å. In the thirty-eighth Si+0.63- site, Si+0.63- is bonded to three Na1+ and four Si+0.63- atoms to form distorted SiNa3Si4 tetrahedra that share corners with three GaSi4 tetrahedra, corners with six SiNa3Si4 tetrahedra, and a faceface with one SiNa3Si4 tetrahedra.

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2020-09-03. Materials Data on Na4Ga4Si19 by Materials Project. https://doi.org/10.17188/1757343

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