Materials Data on Ca2Fe3Si3O14 by Materials Project
Ca2Fe3Si3O14 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Ca–O bond distances ranging from 2.24–2.63 Å. In the second Ca site, Ca is bonded to seven O atoms to form distorted CaO7 pentagonal bipyramids that share corners with five SiO4 tetrahedra, edges with four FeO6 octahedra, and an edgeedge with one SiO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.32–2.58 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four SiO4 tetrahedra, edges with two equivalent FeO6 octahedra, and an edgeedge with one CaO7 pentagonal bipyramid. There are a spread of Fe–O bond distances ranging from 1.86–2.13 Å. In the second Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four SiO4 tetrahedra, edges with two equivalent FeO6 octahedra, and edges with two equivalent CaO7 pentagonal bipyramids. There are a spread of Fe–O bond distances ranging from 1.88–2.14 Å. There are three inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent FeO6 octahedra, corners with three equivalent CaO7 pentagonal bipyramids, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of Si–O bond distances ranging from 1.59–1.70 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with six FeO6 octahedra and corners with two equivalent CaO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 47–61°. There are a spread of Si–O bond distances ranging from 1.64–1.67 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with four equivalent FeO6 octahedra, a cornercorner with one SiO4 tetrahedra, and an edgeedge with one CaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 50–56°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. There are eleven inequivalent O sites. In the first O site, O is bonded in a water-like geometry to two equivalent Fe atoms. In the second O site, O is bonded in a distorted rectangular see-saw-like geometry to one Ca, two equivalent Fe, and one Si atom. In the third O site, O is bonded in a 2-coordinate geometry to one Ca and two Si atoms. In the fourth O site, O is bonded in a bent 150 degrees geometry to one Ca and one Si atom. In the fifth O site, O is bonded in a distorted rectangular see-saw-like geometry to two Ca, one Fe, and one Si atom. In the sixth O site, O is bonded in a trigonal non-coplanar geometry to one Ca and two equivalent Fe atoms. In the seventh O site, O is bonded in a distorted rectangular see-saw-like geometry to one Ca, two equivalent Fe, and one Si atom. In the eighth O site, O is bonded in a trigonal planar geometry to one Ca, one Fe, and one Si atom. In the ninth O site, O is bonded in a water-like geometry to two equivalent Fe atoms. In the tenth O site, O is bonded in a distorted trigonal planar geometry to one Ca, one Fe, and one Si atom. In the eleventh O site, O is bonded in a 3-coordinate geometry to two equivalent Fe and one Si atom.