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Materials Data on Ba2MnSe3 by Materials Project

Ba2MnSe3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to seven Se2- atoms to form distorted BaSe7 pentagonal bipyramids that share corners with three equivalent BaSe7 pentagonal bipyramids, corners with four equivalent MnSe4 tetrahedra, edges with eleven BaSe7 pentagonal bipyramids, and edges with three equivalent MnSe4 tetrahedra. There are a spread of Ba–Se bond distances ranging from 3.25–3.49 Å. In the second Ba2+ site, Ba2+ is bonded to seven Se2- atoms to form distorted BaSe7 pentagonal bipyramids that share corners with seven BaSe7 pentagonal bipyramids, edges with seven BaSe7 pentagonal bipyramids, edges with four equivalent MnSe4 tetrahedra, and faces with two equivalent BaSe7 pentagonal bipyramids. There are a spread of Ba–Se bond distances ranging from 3.32–3.42 Å. Mn2+ is bonded to four Se2- atoms to form MnSe4 tetrahedra that share corners with four equivalent BaSe7 pentagonal bipyramids, corners with two equivalent MnSe4 tetrahedra, and edges with seven BaSe7 pentagonal bipyramids. There are a spread of Mn–Se bond distances ranging from 2.51–2.62 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to five Ba2+ and one Mn2+ atom. In the second Se2- site, Se2- is bonded in a 6-coordinate geometry to four Ba2+ and two equivalent Mn2+ atoms. In the third Se2- site, Se2- is bonded to five Ba2+ and one Mn2+ atom to form a mixture of distorted edge and corner-sharing SeBa5Mn octahedra. The corner-sharing octahedral tilt angles are 23°.

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