Materials Data on Ba5Gd8Mn4O21 by Materials Project

Abstract

Ba5Gd8Mn4O21 crystallizes in the tetragonal I4/m space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.67–3.31 Å. In the second Ba2+ site, Ba2+ is bonded in a distorted q6 geometry to ten O2- atoms. There are two shorter (2.93 Å) and eight longer (2.99 Å) Ba–O bond lengths. There are two inequivalent Gd3+ sites. In the first Gd3+ site, Gd3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Gd–O bond distances ranging from 2.31–2.61 Å. In the second Gd3+ site, Gd3+ is bonded to seven O2- atoms to form distorted GdO7 pentagonal bipyramids that share a cornercorner with one GdO7 pentagonal bipyramid, corners with two equivalent MnO5 trigonal bipyramids, edges with two equivalent MnO5 trigonal bipyramids, and faces with two equivalent GdO7 pentagonal bipyramids. There are a spread of Gd–O bond distances ranging from 2.34–2.49 Å. Mn2+ is bonded to five O2- atoms to form MnO5 trigonal bipyramids that share corners with two equivalent GdO7 pentagonal bipyramids and edges with two equivalent GdO7 pentagonal bipyramids. There are a spread of Mn–O bond distances ranging from 2.07–2.17 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, three Gd3+, and one Mn2+ atom. In the second O2- site, O2- is bonded in a 6-coordinate geometry to two Ba2+, three Gd3+, and one Mn2+ atom. In the third O2- site, O2- is bonded to four equivalent Ba2+, one Gd3+, and one Mn2+ atom to form a mixture of distorted edge and corner-sharing OBa4GdMn octahedra. The corner-sharing octahedral tilt angles are 7°. In the fourth O2- site, O2- is bonded to two equivalent Ba2+ and four equivalent Gd3+ atoms to form distorted corner-sharing OBa2Gd4 octahedra. The corner-sharing octahedral tilt angles are 0°.