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Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Ca2MnFeSi4H3O14H2O crystallizes in the triclinic P-1 space group. The structure is three-dimensional and consists of two water molecules and one Ca2MnFeSi4H3O14 framework. In the Ca2MnFeSi4H3O14 framework, there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.27–2.55 Å. In the second Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.69 Å. Mn2+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six SiO4 tetrahedra and an edgeedge with one FeO6 octahedra. There are a spread of Mn–O bond distances ranging from 2.13–2.45 Å. Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six SiO4 tetrahedra, an edgeedge with one MnO6 octahedra, and an edgeedge with one FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.99–2.09 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 corners with two equivalent MnO6 octahedra, corners with three equivalent FeO6 octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–54°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one FeO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Si–O bond distances ranging from 1.62–1.68 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent MnO6 octahedra, corners with two equivalent FeO6 octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–55°. There are a spread of Si–O bond distances ranging from 1.64–1.67 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent MnO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–57°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. In the third H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.03 Å) and one longer (1.59 Å) H–O bond length. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted tetrahedral geometry to two Ca2+, one Mn2+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Si4+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Mn2+, one Si4+, and one H1+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one Fe3+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a distorted water-like geometry to two Ca2+ and two H1+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mn2+, one Fe3+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ca2+ and two Si4+ atoms. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+, one Mn2+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Si4+ atoms. In the eleventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ca2+, one Mn2+, one Fe3+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one Mn2+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Fe3+ and one Si4+ atom. In the fourteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Fe3+, one Si4+, and one H1+ atom.