DOE OSTI2020
Sr7LaCu4(BiO3)8 is Pb (Zr_0.50 Ti_0.48) O_3-derived structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are seven inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.48–3.05 Å. In the second Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.40–2.79 Å. In the third Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.41–2.94 Å. In the fourth Sr2+ site, Sr2+ is bonded to six O2- atoms to form distorted SrO6 pentagonal pyramids that share corners with two BiO5 square pyramids, a cornercorner with one CuO5 trigonal bipyramid, and a cornercorner with one BiO5 trigonal bipyramid. There are a spread of Sr–O bond distances ranging from 2.42–2.87 Å. In the fifth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.48–3.11 Å. In the sixth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.32–3.17 Å. In the seventh Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.50–2.78 Å. La3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of La–O bond distances ranging from 2.33–2.80 Å. There are four inequivalent Cu+1.75+ sites. In the first Cu+1.75+ site, Cu+1.75+ is bonded in a 3-coordinate geometry to three O2- atoms. There are two shorter (1.88 Å) and one longer (2.33 Å) Cu–O bond lengths. In the second Cu+1.75+ site, Cu+1.75+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.80 Å) and one longer (1.87 Å) Cu–O bond length. In the third Cu+1.75+ site, Cu+1.75+ is bonded to five O2- atoms to form distorted CuO5 trigonal bipyramids that share a cornercorner with one SrO6 pentagonal pyramid, a cornercorner with one BiO5 trigonal bipyramid, and an edgeedge with one BiO5 square pyramid. There are a spread of Cu–O bond distances ranging from 1.96–2.62 Å. In the fourth Cu+1.75+ site, Cu+1.75+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.84 Å) and one longer (1.86 Å) Cu–O bond length. There are eight inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to five O2- atoms to form distorted BiO5 trigonal bipyramids that share a cornercorner with one SrO6 pentagonal pyramid, a cornercorner with one CuO5 trigonal bipyramid, and an edgeedge with one BiO5 square pyramid. There are a spread of Bi–O bond distances ranging from 2.22–2.72 Å. In the second 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 2.13–2.92 Å. In the third Bi3+ site, Bi3+ is bonded in a 3-coordinate geometry to three O2- atoms. There are one shorter (2.12 Å) and two longer (2.20 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 2.16–2.83 Å. In the fifth Bi3+ site, Bi3+ is bonded to five O2- atoms to form distorted BiO5 square pyramids that share a cornercorner with one SrO6 pentagonal pyramid, a cornercorner with one BiO5 square pyramid, an edgeedge with one CuO5 trigonal bipyramid, and an edgeedge with one BiO5 trigonal bipyramid. There are a spread of Bi–O bond distances ranging from 2.19–2.62 Å. In the sixth 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 2.14–2.99 Å. In the seventh Bi3+ site, Bi3+ is bonded to five O2- atoms to form distorted BiO5 square pyramids that share a cornercorner with one SrO6 pentagonal pyramid and a cornercorner with one BiO5 square pyramid. There are a spread of Bi–O bond distances ranging from 2.20–2.67 Å. In the eighth Bi3+ site, Bi3+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Bi–O bond distances ranging from 2.19–2.69 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+, one La3+, and two Bi3+ atoms. In the second O2- site, O2- is bonded to four Sr2+ and one Bi3+ atom to form OSr4Bi trigonal bipyramids that share a cornercorner with one OSr3CuBi2 octahedra, a cornercorner with one OSr3Bi tetrahedra, a cornercorner with one OSr2CuBi2 trigonal bipyramid, and an edgeedge with one OSr2Bi3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 56°. In the third O2- site, O2- is bonded in a 6-coordinate geometry to three Sr2+, one La3+, and two Bi3+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+, one Cu+1.75+, and two Bi3+ atoms. In the fifth O2- site, O2- is bonded to two Sr2+ and three Bi3+ atoms to form distorted OSr2Bi3 trigonal bipyramids that share a cornercorner with one OSr2CuBi2 trigonal bipyramid, an edgeedge with one OSr4Bi trigonal bipyramid, and a faceface with one OSr3CuBi2 octahedra. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to two Sr2+ and three Bi3+ atoms. In the seventh O2- site, O2- is bonded to two Sr2+, one Cu+1.75+, and two Bi3+ atoms to form distorted OSr2CuBi2 trigonal bipyramids that share corners with two OSr4Bi trigonal bipyramids and an edgeedge with one OSr3Bi tetrahedra. In the eighth O2- site, O2- is bonded in a 5-coordinate geometry to three Sr2+, one Bi3+, and one O2- atom. The O–O bond length is 1.52 Å. In the ninth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Sr2+, one Cu+1.75+, and two Bi3+ atoms. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to one La3+, one Cu+1.75+, and two Bi3+ atoms. In the eleventh O2- site, O2- is bonded in a 5-coordinate geometry to three Sr2+ and two Bi3+ atoms. In the twelfth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Sr2+ and one Cu+1.75+ atom. In the thirteenth O2- site, O2- is bonded to three Sr2+ and one Bi3+ atom to form distorted OSr3Bi tetrahedra that share a cornercorner with one OSr3CuBi2 octahedra, a cornercorner with one OSr4Bi trigonal bipyramid, and an edgeedge with one OSr2CuBi2 trigonal bipyramid. The corner-sharing octahedral tilt angles are 28°. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+, one Bi3+, and one O2- atom. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+, one Cu+1.75+, and two Bi3+ atoms. In the sixteenth O2- site, O2- is bonded in a 5-coordinate geometry to two Sr2+, one Cu+1.75+, and two Bi3+ atoms. In the seventeenth O2- site, O2- is bonded to three Sr2+, one Cu+1.75+, and two Bi3+ atoms to form distorted OSr3CuBi2 octahedra that share a cornercorner with one OSr3Bi tetrahedra, a cornercorner with one OSr4Bi trigonal bipyramid, and a faceface with one OSr2Bi3 trigonal bipyramid. In the eighteenth O2- site, O2- is bonded in a 5-coordinate geometry to two Sr2+, one La3+, one Cu+1.75+, and one Bi3+ atom. In the nineteenth O2- site, O2- is bonded in a 5-coordinate geometry to one Sr2+, one La3+, one Cu+1.75+, and two Bi3+ atoms. In the twentieth O2- site, O2- is bonded in a trigonal planar geometry to one Sr2+ and two Bi3+ atoms. In the twenty-first O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+, one Cu+1.75+, and two Bi3+ atoms. In the twenty-second O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Sr2+, one La3+, and one Bi3+ atom. In the twenty-third O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+, one La3+, one Cu+1.75+, and one Bi3+ atom. In the twenty-fourth O2- site, O2- is bonded in a distorted T-shaped geometry to one Sr2+ and two Bi3+ atoms.