Materials Data on BaSr2Mn2(Si2O7)2 by Materials Project

Abstract

BaSr2Mn2(Si2O7)2 is Esseneite-derived structured and crystallizes in the monoclinic C2 space group. The structure is three-dimensional. Ba2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ba–O bond distances ranging from 2.70–3.05 Å. Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.46–2.79 Å. There are two inequivalent Mn3+ sites. In the first Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with four SiO4 tetrahedra and edges with two equivalent MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.89–2.18 Å. In the second Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with four equivalent SiO4 tetrahedra and edges with two equivalent MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.92–2.34 Å. There are two 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 MnO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are a spread of Si–O bond distances ranging from 1.61–1.70 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MnO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–68°. There are a spread of Si–O bond distances ranging from 1.62–1.70 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Sr2+ and two Si4+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Mn3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Ba2+, two equivalent Sr2+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Sr2+, and two Mn3+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, one Sr2+, one Mn3+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+, two Mn3+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sr2+ and two Si4+ atoms.