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DOE OSTI · 1290774

Materials Data on Ca4Bi6O13 by Materials Project

Abstract

Ca4Bi6O13 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are four inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted CaO7 pentagonal bipyramids that share corners with four CaO7 pentagonal bipyramids, a cornercorner with one BiO5 square pyramid, edges with two CaO7 pentagonal bipyramids, edges with two BiO5 square pyramids, and faces with two CaO7 pentagonal bipyramids. There are a spread of Ca–O bond distances ranging from 2.39–2.54 Å. In the second Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted CaO7 pentagonal bipyramids that share corners with four CaO7 pentagonal bipyramids, a cornercorner with one BiO5 square pyramid, edges with two CaO7 pentagonal bipyramids, edges with two BiO5 square pyramids, and faces with two CaO7 pentagonal bipyramids. There are a spread of Ca–O bond distances ranging from 2.41–2.55 Å. In the third Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted CaO7 pentagonal bipyramids that share corners with four CaO7 pentagonal bipyramids, a cornercorner with one BiO5 square pyramid, edges with two CaO7 pentagonal bipyramids, edges with two BiO5 square pyramids, and faces with two CaO7 pentagonal bipyramids. There are a spread of Ca–O bond distances ranging from 2.39–2.55 Å. In the fourth Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted CaO7 pentagonal bipyramids that share corners with four CaO7 pentagonal bipyramids, a cornercorner with one BiO5 square pyramid, edges with two CaO7 pentagonal bipyramids, edges with two BiO5 square pyramids, and faces with two CaO7 pentagonal bipyramids. There are a spread of Ca–O bond distances ranging from 2.40–2.55 Å. There are eight inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to five O2- atoms to form BiO5 square pyramids that share corners with two CaO7 pentagonal bipyramids and edges with four CaO7 pentagonal bipyramids. There are a spread of Bi–O bond distances ranging from 2.10–2.45 Å. In the second Bi3+ site, Bi3+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are one shorter (2.10 Å) and two longer (2.11 Å) Bi–O bond lengths. In the third Bi3+ site, Bi3+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are one shorter (2.10 Å) and two longer (2.11 Å) Bi–O bond lengths. In the fourth Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Bi–O bond distances ranging from 2.12–3.05 Å. In the fifth Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Bi–O bond distances ranging from 2.13–2.85 Å. In the sixth Bi3+ site, Bi3+ is bonded to five O2- atoms to form BiO5 square pyramids that share corners with two CaO7 pentagonal bipyramids and edges with four CaO7 pentagonal bipyramids. There are a spread of Bi–O bond distances ranging from 2.10–2.45 Å. In the seventh Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Bi–O bond distances ranging from 2.13–2.85 Å. In the eighth Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Bi–O bond distances ranging from 2.12–3.05 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to four Bi3+ atoms. In the second O2- site, O2- is bonded in a 5-coordinate geometry to four Ca2+ and one Bi3+ atom. In the third O2- site, O2- is bonded to two Ca2+ and two Bi3+ atoms to form distorted OCa2Bi2 trigonal pyramids that share a cornercorner with one OCa4Bi trigonal bipyramid, corners with four OCa2Bi2 trigonal pyramids, and edges with two OCa4Bi trigonal bipyramids. In the fourth O2- site, O2- is bonded to two Ca2+ and two Bi3+ atoms to form OCa2Bi2 trigonal pyramids that share a cornercorner with one OCa4Bi trigonal bipyramid, corners with four OCa2Bi2 trigonal pyramids, and edges with two OCa4Bi trigonal bipyramids. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ca2+ and three Bi3+ atoms. In the sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ca2+ and three Bi3+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to four Bi3+ atoms. In the eighth O2- site, O2- is bonded in a 5-coordinate geometry to four Ca2+ and one Bi3+ atom. In the ninth O2- site, O2- is bonded to four Ca2+ and one Bi3+ atom to form distorted OCa4Bi trigonal bipyramids that share corners with two equivalent OCa2Bi2 trigonal pyramids, edges with two OCa4Bi trigonal bipyramids, and edges with four OCa2Bi2 trigonal pyramids. In the tenth O2- site, O2- is bonded to four Ca2+ and one Bi3+ atom to form distorted OCa4Bi trigonal bipyramids that share corners with two equivalent OCa2Bi2 trigonal pyramids, edges with two OCa4Bi trigonal bipyramids, and edges with four OCa2Bi2 trigonal pyramids. In the eleventh O2- site, O2- is bonded to two Ca2+ and two Bi3+ atoms to form OCa2Bi2 trigonal pyramids that share a cornercorner with one OCa4Bi trigonal bipyramid, corners with four OCa2Bi2 trigonal pyramids, and edges with two OCa4Bi trigonal bipyramids. In the twelfth O2- site, O2- is bonded to two Ca2+ and two Bi3+ atoms to form distorted OCa2Bi2 trigonal pyramids that share a cornercorner with one OCa4Bi trigonal bipyramid, corners with four OCa2Bi2 trigonal pyramids, and edges with two OCa4Bi trigonal bipyramids. In the thirteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ca2+ and three Bi3+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ca2+ and three Bi3+ atoms. In the fifteenth O2- site, O2- is bonded to four Ca2+ and one Bi3+ atom to form distorted OCa4Bi trigonal bipyramids that share corners with two equivalent OCa2Bi2 trigonal pyramids, edges with two OCa4Bi trigonal bipyramids, and edges with four OCa2Bi2 trigonal pyramids. In the sixteenth O2- site, O2- is bonded to four Ca2+ and one Bi3+ atom to form distorted OCa4Bi trigonal bipyramids that share corners with two equivalent OCa2Bi2 trigonal pyramids, edges with two OCa4Bi trigonal bipyramids, and edges with four OCa2Bi2 trigonal pyramids.

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2020-07-15. Materials Data on Ca4Bi6O13 by Materials Project. https://doi.org/10.17188/1290774

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