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DOE OSTI · 1193839

Materials Data on HoMnO3 by Materials Project

Abstract

HoMnO3 crystallizes in the hexagonal P6_3cm space group. The structure is three-dimensional. there are two inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to seven O2- atoms to form distorted HoO7 pentagonal bipyramids that share corners with three equivalent MnO5 trigonal bipyramids, edges with six HoO7 pentagonal bipyramids, and edges with three equivalent MnO5 trigonal bipyramids. There are a spread of Ho–O bond distances ranging from 2.28–2.42 Å. In the second Ho3+ site, Ho3+ is bonded to seven O2- atoms to form distorted HoO7 pentagonal bipyramids that share corners with three equivalent MnO5 trigonal bipyramids, edges with six equivalent HoO7 pentagonal bipyramids, and edges with three equivalent MnO5 trigonal bipyramids. There are a spread of Ho–O bond distances ranging from 2.29–2.33 Å. Mn3+ is bonded to five O2- atoms to form MnO5 trigonal bipyramids that share corners with three HoO7 pentagonal bipyramids, corners with six equivalent MnO5 trigonal bipyramids, and edges with three HoO7 pentagonal bipyramids. There are a spread of Mn–O bond distances ranging from 1.91–2.09 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to one Ho3+ and three equivalent Mn3+ atoms to form OHoMn3 trigonal pyramids that share corners with six equivalent OHo3Mn tetrahedra, corners with six OHoMn3 trigonal pyramids, and edges with three equivalent OHo3Mn tetrahedra. In the second O2- site, O2- is bonded to one Ho3+ and three equivalent Mn3+ atoms to form OHoMn3 trigonal pyramids that share corners with six equivalent OHo3Mn tetrahedra, corners with six equivalent OHoMn3 trigonal pyramids, and edges with three equivalent OHo3Mn tetrahedra. In the third O2- site, O2- is bonded to three Ho3+ and one Mn3+ atom to form distorted OHo3Mn tetrahedra that share corners with ten OHo3Mn tetrahedra, corners with four equivalent OHoMn3 trigonal pyramids, edges with three equivalent OHo3Mn tetrahedra, and an edgeedge with one OHoMn3 trigonal pyramid. In the fourth O2- site, O2- is bonded to three Ho3+ and one Mn3+ atom to form OHo3Mn tetrahedra that share corners with ten OHo3Mn tetrahedra, corners with two equivalent OHoMn3 trigonal pyramids, edges with three equivalent OHo3Mn tetrahedra, and edges with two equivalent OHoMn3 trigonal pyramids.

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2020-07-15. Materials Data on HoMnO3 by Materials Project. https://doi.org/10.17188/1193839

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