DOI: 10.17188/1683532
title: Materials Data on NaCa3MgFe(Si2O7)2 by Materials Project

description: NaCa3MgFe(Si2O7)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.44–2.98 Å. There are three inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.36–2.91 Å. In the second Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.40–2.72 Å. In the third Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.36–2.78 Å. Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with four SiO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 1.94–1.96 Å. Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with four SiO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.88–1.90 Å. There are four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one MgO4 tetrahedra, a cornercorner with one FeO4 tetrahedra, and a cornercorner with one SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.69 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one MgO4 tetrahedra, a cornercorner with one FeO4 tetrahedra, and a cornercorner with one SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one MgO4 tetrahedra, a cornercorner with one FeO4 tetrahedra, and a cornercorner with one SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one MgO4 tetrahedra, a cornercorner with one FeO4 tetrahedra, and a cornercorner with one SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two Ca2+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two Ca2+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three Ca2+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two Ca2+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Ca2+, one Mg2+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Ca2+, one Fe3+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Mg2+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+, one Fe3+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Ca2+, one Mg2+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+, one Fe3+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Mg2+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Ca2+, one Fe3+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Ca2+, and two Si4+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted tetrahedral geometry to two Ca2+ and two Si4+ atoms.