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DOE OSTI · 1292226

Materials Data on Ca3Mn4O8 by Materials Project

Abstract

Ca3Mn4O8 crystallizes in the monoclinic Pc space group. The structure is three-dimensional. there are six inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share corners with four CaO6 octahedra, corners with five MnO5 square pyramids, a cornercorner with one MnO5 trigonal bipyramid, edges with two equivalent CaO6 octahedra, an edgeedge with one MnO5 square pyramid, edges with two MnO5 trigonal bipyramids, and a faceface with one MnO5 square pyramid. The corner-sharing octahedra tilt angles range from 40–64°. There are a spread of Ca–O bond distances ranging from 2.26–2.52 Å. In the second Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share corners with four CaO6 octahedra, corners with six MnO5 square pyramids, edges with two equivalent CaO6 octahedra, edges with three MnO5 square pyramids, and a faceface with one MnO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 39–61°. There are a spread of Ca–O bond distances ranging from 2.24–2.49 Å. In the third Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share corners with four CaO6 octahedra, corners with three MnO5 square pyramids, corners with three MnO5 trigonal bipyramids, edges with two equivalent CaO6 octahedra, edges with two MnO5 square pyramids, an edgeedge with one MnO5 trigonal bipyramid, and a faceface with one MnO5 square pyramid. The corner-sharing octahedra tilt angles range from 46–56°. There are a spread of Ca–O bond distances ranging from 2.22–2.51 Å. In the fourth Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share corners with four CaO6 octahedra, corners with four MnO5 square pyramids, corners with two equivalent MnO5 trigonal bipyramids, edges with two equivalent CaO6 octahedra, edges with three MnO5 square pyramids, and a faceface with one MnO5 square pyramid. The corner-sharing octahedra tilt angles range from 32–67°. There are a spread of Ca–O bond distances ranging from 2.27–2.48 Å. In the fifth Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share corners with eight CaO6 octahedra, corners with five MnO5 square pyramids, a cornercorner with one MnO5 trigonal bipyramid, edges with two MnO5 square pyramids, and edges with two MnO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 32–64°. There are a spread of Ca–O bond distances ranging from 2.29–2.60 Å. In the sixth Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share corners with eight CaO6 octahedra, corners with four MnO5 square pyramids, corners with two equivalent MnO5 trigonal bipyramids, and edges with four MnO5 square pyramids. The corner-sharing octahedra tilt angles range from 40–67°. There are a spread of Ca–O bond distances ranging from 2.34–2.60 Å. There are eight inequivalent Mn+2.50+ sites. In the first Mn+2.50+ site, Mn+2.50+ is bonded to five O2- atoms to form MnO5 square pyramids that share corners with five CaO6 octahedra, corners with two MnO5 square pyramids, corners with two equivalent MnO5 trigonal bipyramids, edges with two CaO6 octahedra, edges with two equivalent MnO5 square pyramids, and a faceface with one CaO6 octahedra. The corner-sharing octahedra tilt angles range from 35–83°. There are a spread of Mn–O bond distances ranging from 1.95–2.23 Å. In the second Mn+2.50+ site, Mn+2.50+ is bonded to five O2- atoms to form distorted MnO5 trigonal bipyramids that share corners with five CaO6 octahedra, corners with four MnO5 square pyramids, edges with two CaO6 octahedra, edges with two equivalent MnO5 square pyramids, and a faceface with one CaO6 octahedra. The corner-sharing octahedra tilt angles range from 31–79°. There are a spread of Mn–O bond distances ranging from 2.09–2.37 Å. In the third Mn+2.50+ site, Mn+2.50+ is bonded to five O2- atoms to form distorted MnO5 square pyramids that share corners with five CaO6 octahedra, corners with two MnO5 square pyramids, corners with two equivalent MnO5 trigonal bipyramids, edges with two CaO6 octahedra, edges with two equivalent MnO5 square pyramids, and a faceface with one CaO6 octahedra. The corner-sharing octahedra tilt angles range from 27–78°. There are a spread of Mn–O bond distances ranging from 2.07–2.35 Å. In the fourth Mn+2.50+ site, Mn+2.50+ is bonded to five O2- atoms to form MnO5 square pyramids that share corners with five CaO6 octahedra, corners with four MnO5 square pyramids, edges with two CaO6 octahedra, edges with two equivalent MnO5 trigonal bipyramids, and a faceface with one CaO6 octahedra. The corner-sharing octahedra tilt angles range from 38–82°. There are a spread of Mn–O bond distances ranging from 1.95–2.24 Å. In the fifth Mn+2.50+ site, Mn+2.50+ is bonded to five O2- atoms to form distorted MnO5 trigonal bipyramids that share corners with four CaO6 octahedra, corners with four MnO5 square pyramids, edges with three CaO6 octahedra, and edges with two equivalent MnO5 square pyramids. The corner-sharing octahedra tilt angles range from 56–79°. There are a spread of Mn–O bond distances ranging from 1.98–2.49 Å. In the sixth Mn+2.50+ site, Mn+2.50+ is bonded to five O2- atoms to form distorted MnO5 square pyramids that share corners with four CaO6 octahedra, corners with three MnO5 square pyramids, a cornercorner with one MnO5 trigonal bipyramid, edges with three CaO6 octahedra, and edges with two equivalent MnO5 square pyramids. The corner-sharing octahedra tilt angles range from 43–72°. There are a spread of Mn–O bond distances ranging from 1.94–2.39 Å. In the seventh Mn+2.50+ site, Mn+2.50+ is bonded to five O2- atoms to form distorted MnO5 square pyramids that share corners with four CaO6 octahedra, corners with three MnO5 square pyramids, a cornercorner with one MnO5 trigonal bipyramid, edges with three CaO6 octahedra, and edges with two equivalent MnO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 50–74°. There are a spread of Mn–O bond distances ranging from 2.07–2.33 Å. In the eighth Mn+2.50+ site, Mn+2.50+ is bonded to five O2- atoms to form distorted MnO5 square pyramids that share corners with four CaO6 octahedra, corners with two equivalent MnO5 square pyramids, corners with two equivalent MnO5 trigonal bipyramids, edges with three CaO6 octahedra, and edges with two equivalent MnO5 square pyramids. The corner-sharing octahedra tilt angles range from 64–77°. There are a spread of Mn–O bond distances ranging from 2.11–2.27 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded to two Ca2+ and three Mn+2.50+ atoms to form distorted OCa2Mn3 trigonal bipyramids that share corners with three OCa3Mn2 trigonal bipyramids, corners with four OCa2Mn2 trigonal pyramids, and edges with four OCa3Mn2 trigonal bipyramids. In the second O2- site, O2- is bonded in a 5-coordinate geometry to three Ca2+ and two Mn+2.50+ atoms. In the third O2- site, O2- is bonded in a 5-coordinate geometry to three Ca2+ and two Mn+2.50+ atoms. In the fourth O2- site, O2- is bonded to two Ca2+ and three Mn+2.50+ atoms to form distorted OCa2Mn3 trigonal bipyramids that share corners with six OCa3Mn2 trigonal bipyramids, corners with four OCa2Mn2 trigonal pyramids, and edges with two OCa3Mn2 trigonal bipyramids. In the fifth O2- site, O2- is bonded to two Ca2+ and two Mn+2.50+ atoms to form OCa2Mn2 trigonal pyramids that share corners with eight OCa3Mn2 trigonal bipyramids, a cornercorner with one OCa2Mn2 trigonal pyramid, edges with two OCa2Mn3 trigonal bipyramids, and an edgeedge with one OCa2Mn2 trigonal pyramid. In the sixth O2- site, O2- is bonded to two Ca2+ and two Mn+2.50+ atoms to form OCa2Mn2 trigonal pyramids that share corners with seven OCa3Mn2 trigonal bipyramids, a cornercorner with one OCa2Mn2 trigonal pyramid, an edgeedge with one OCa2Mn3 trigonal bipyramid, and an edgeedge with one OCa2Mn2 trigonal pyramid. In the seventh O2- site, O2- is bonded to two Ca2+ and two Mn+2.50+ atoms to form OCa2Mn2 trigonal pyramids that share corners with eight OCa3Mn2 trigonal bipyramids, a cornercorner with one OCa2Mn2 trigonal pyramid, edges with two OCa2Mn3 trigonal bipyramids, and an edgeedge with one OCa2Mn2 trigonal pyramid. In the eighth O2- site, O2- is bonded to two Ca2+ and two Mn+2.50+ atoms to form distorted OCa2Mn2 trigonal pyramids that share corners with eight OCa3Mn2 trigonal bipyramids, a cornercorner with one OCa2Mn2 trigonal pyramid, and an edgeedge with one OCa2Mn2 trigonal pyramid. In the ninth O2- site, O2- is bonded in a 5-coordinate geometry to two Ca2+ and three Mn+2.50+ atoms. In the tenth O2- site, O2- is bonded to three Ca2+ and two Mn+2.50+ atoms to form distorted OCa3Mn2 trigonal bipyramids that share corners with four OCa2Mn3 trigonal bipyramids, corners with four OCa2Mn2 trigonal pyramids, and edges with five OCa2Mn3 trigonal bipyramids. In the eleventh O2- site, O2- is bonded to three Ca2+ and two Mn+2.50+ atoms to form distorted OCa3Mn2 trigonal bipyramids that share corners with three OCa2Mn3 trigonal bipyramids, corners with four OCa2Mn2 trigonal pyramids, and edges with two OCa2Mn3 trigonal bipyramids. In the twelfth O2- site, O2- is bonded to two Ca2+ and three Mn+2.50+ atoms to form distorted OCa2Mn3 trigonal bipyramids that share corners with four OCa2Mn3 trigonal bipyramids, edges with five OCa3Mn2 trigonal bipyramids, and edges with two OCa2Mn2 trigonal pyramids. In the thirteenth O2- site, O2- is bonded to two Ca2+ and three Mn+2.50+ atoms to form distorted OCa2Mn3 trigonal bipyramids that share corners with two OCa3Mn2 trigonal bipyramids, corners with five OCa2Mn2 trigonal pyramids, edges with two OCa3Mn2 trigonal bipyramids, and an edgeedge with one OCa2Mn2 trigonal pyramid. In the fourteenth O2- site, O2- is bonded to two Ca2+ and three Mn+2.50+ atoms to form distorted OCa2Mn3 trigonal bipyramids that share corners with four OCa3Mn2 trigonal bipyramids, corners with five OCa2Mn2 trigonal pyramids, edges with four OCa3Mn2 trigonal bipyramids, and an edgeedge with one OCa2Mn2 trigonal pyramid. In the fifteenth O2- site, O2- is bonded in a 5-coordinate geometry to two Ca2+ and three Mn+2.50+ atoms. In the sixteenth O2- site, O2- is bonded to two Ca2+ and three Mn+2.50+ atoms to form distorted OCa2Mn3 trigonal bipyramids that share corners with four OCa3Mn2 trigonal bipyramids, corners with five OCa2Mn2 trigonal pyramids, edges with four OCa3Mn2 trigonal bipyramids, and an edgeedge with one OCa2Mn2 trigonal pyramid.

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2020-05-02. Materials Data on Ca3Mn4O8 by Materials Project. https://doi.org/10.17188/1292226

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