Materials Data on NaMg3(SiO3)4 by Materials Project
NaMg3(SiO3)4 is Esseneite-like structured and crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded in a 2-coordinate geometry to eight O atoms. There are a spread of Na–O bond distances ranging from 2.41–2.94 Å. In the second Na site, Na is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Na–O bond distances ranging from 2.28–2.85 Å. There are six inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with three MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.00–2.20 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra, edges with three MgO6 octahedra, and edges with two equivalent MgO5 square pyramids. There are a spread of Mg–O bond distances ranging from 2.03–2.17 Å. In the third Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with four SiO4 tetrahedra and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.10–2.29 Å. In the fourth Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with four SiO4 tetrahedra and edges with five MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.99–2.17 Å. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four SiO4 tetrahedra, edges with five MgO6 octahedra, and an edgeedge with one MgO5 square pyramid. There are a spread of Mg–O bond distances ranging from 1.98–2.14 Å. In the sixth Mg site, Mg is bonded to five O atoms to form distorted MgO5 square pyramids that share corners with four SiO4 tetrahedra, edges with three MgO6 octahedra, and an edgeedge with one SiO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 2.03–2.50 Å. There are eight inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra, a cornercorner with one MgO5 square pyramid, and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 42–55°. There is two shorter (1.62 Å) and two longer (1.69 Å) Si–O bond length. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra, a cornercorner with one MgO5 square pyramid, and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–58°. There are a spread of Si–O bond distances ranging from 1.58–1.70 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra, corners with two equivalent SiO4 tetrahedra, and an edgeedge with one MgO5 square pyramid. The corner-sharing octahedra tilt angles range from 33–54°. There are a spread of Si–O bond distances ranging from 1.62–1.69 Å. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra, a cornercorner with one MgO5 square pyramid, and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 31–58°. There are a spread of Si–O bond distances ranging from 1.58–1.68 Å. In the fifth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra, a cornercorner with one MgO5 square pyramid, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 58–60°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the sixth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 58–62°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. In the seventh Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–62°. There are a spread of Si–O bond distances ranging from 1.61–1.67 Å. In the eighth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 57–62°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. There are twenty-four inequivalent O sites. In the first O site, O is bonded in a distorted trigonal non-coplanar geometry to one Na and two Si atoms. In the second O site, O is bonded in a 4-coordinate geometry to three Mg and one O atom. The O–O bond length is 1.59 Å. In the third O site, O is bonded in a distorted bent 120 degrees geometry to one Na and two Si atoms. In the fourth O site, O is bonded in a 2-coordinate geometry to two Na and two Si atoms. In the fifth O site, O is bonded in a 2-coordinate geometry to one Na and two Si atoms. In the sixth O site, O is bonded in a 2-coordinate geometry to one Na and two Si atoms. In the seventh O site, O is bonded to three Mg and one Si atom to form a mixture of distorted edge and corner-sharing OMg3Si trigonal pyramids. In the eighth O site, O is bonded to three Mg and one Si atom to form a mixture of distorted edge and corner-sharing OMg3Si tetrahedra. In the ninth O site, O is bonded in a distorted rectangular see-saw-like geometry to one Na, two Mg, and one Si atom. In the tenth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the eleventh O site, O is bonded in a 3-coordinate geometry to one Mg and two Si atoms. In the twelfth O site, O is bonded in a 3-coordinate geometry to one Na and two Si atoms. In the thirteenth O site, O is bonded in a distorted trigonal planar geometry to two Mg and one Si atom. In the fourteenth O site, O is bonded in a distorted T-shaped geometry to one Na, one Mg, and one Si atom. In the fifteenth O site, O is bonded in a distorted T-shaped geometry to two Mg and one Si atom. In the sixteenth O site, O is bonded in a distorted T-shaped geometry to one Na, one Mg, and one Si atom. In the seventeenth O site, O is bonded in a rectangular see-saw-like geometry to one Na, two Mg, and one Si atom. In the eighteenth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the nineteenth O site, O is bonded in a 2-coordinate geometry to one Na and two Si atoms. In the twentieth O site, O is bonded in a 2-coordinate geometry to two Na and two Si atoms. In the twenty-first O site, O is bonded in a 4-coordinate geometry to three Mg and one O atom. In the twenty-second O site, O is bonded in a distorted trigonal non-coplanar geometry to one Na and two Si atoms. In the twenty-third O site, O is bonded to three Mg and one Si atom to form a mixture of distorted edge and corner-sharing OMg3Si trigonal pyramids. In the twenty-fourth O site, O is bonded to three Mg and one Si atom to form a mixture of distorted edge and corner-sharing OMg3Si trigonal pyramids.