DOE OSTI2020
BaMg2V6(Cu4O13)2 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.72–3.21 Å. There are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six VO4 tetrahedra, edges with two equivalent CuO6 octahedra, and an edgeedge with one CuO5 trigonal bipyramid. There are a spread of Mg–O bond distances ranging from 2.03–2.23 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six VO4 tetrahedra, edges with two equivalent CuO6 octahedra, and an edgeedge with one CuO5 trigonal bipyramid. There are a spread of Mg–O bond distances ranging from 2.04–2.37 Å. There are six inequivalent V5+ sites. In the first V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share a cornercorner with one MgO6 octahedra, corners with two equivalent CuO6 octahedra, and corners with four CuO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 48°. There are a spread of V–O bond distances ranging from 1.70–1.79 Å. In the second V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share a cornercorner with one MgO6 octahedra, corners with two equivalent CuO6 octahedra, and corners with four CuO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 42–51°. There are a spread of V–O bond distances ranging from 1.70–1.78 Å. In the third V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with three MgO6 octahedra and corners with four CuO6 octahedra. The corner-sharing octahedra tilt angles range from 47–67°. There are a spread of V–O bond distances ranging from 1.69–1.92 Å. In the fourth V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with three MgO6 octahedra and corners with four CuO6 octahedra. The corner-sharing octahedra tilt angles range from 49–69°. There are a spread of V–O bond distances ranging from 1.69–1.94 Å. In the fifth V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with two equivalent MgO6 octahedra, corners with four CuO6 octahedra, and corners with four CuO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 35–67°. There are a spread of V–O bond distances ranging from 1.71–1.81 Å. In the sixth V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with two equivalent MgO6 octahedra, corners with four CuO6 octahedra, and corners with four CuO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 34–67°. There are a spread of V–O bond distances ranging from 1.68–1.83 Å. There are six inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded to six O2- atoms to form distorted CuO6 octahedra that share corners with five VO4 tetrahedra, a cornercorner with one CuO5 trigonal bipyramid, an edgeedge with one MgO6 octahedra, edges with two equivalent CuO6 octahedra, and edges with two CuO5 trigonal bipyramids. There are a spread of Cu–O bond distances ranging from 1.94–2.70 Å. In the second Cu2+ site, Cu2+ is bonded to six O2- atoms to form distorted CuO6 octahedra that share corners with five VO4 tetrahedra, a cornercorner with one CuO5 trigonal bipyramid, an edgeedge with one MgO6 octahedra, edges with two equivalent CuO6 octahedra, and edges with two CuO5 trigonal bipyramids. There are a spread of Cu–O bond distances ranging from 1.93–2.68 Å. In the third Cu2+ site, Cu2+ is bonded to five O2- atoms to form distorted CuO5 trigonal bipyramids that share corners with four VO4 tetrahedra, edges with two equivalent CuO6 octahedra, and an edgeedge with one CuO5 trigonal bipyramid. There are a spread of Cu–O bond distances ranging from 1.92–2.10 Å. In the fourth Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 trigonal bipyramids that share corners with four VO4 tetrahedra, edges with two equivalent CuO6 octahedra, and an edgeedge with one CuO5 trigonal bipyramid. There are a spread of Cu–O bond distances ranging from 1.88–2.04 Å. In the fifth Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 trigonal bipyramids that share corners with two equivalent CuO6 octahedra, corners with four VO4 tetrahedra, an edgeedge with one MgO6 octahedra, edges with two equivalent CuO6 octahedra, and an edgeedge with one CuO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 55°. There are a spread of Cu–O bond distances ranging from 1.96–2.18 Å. In the sixth Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 trigonal bipyramids that share corners with two equivalent CuO6 octahedra, corners with four VO4 tetrahedra, an edgeedge with one MgO6 octahedra, edges with two equivalent CuO6 octahedra, and an edgeedge with one CuO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 56°. There are a spread of Cu–O bond distances ranging from 1.96–2.19 Å. There are twenty inequivalent O2- sites. In the first O2- site, O2- is bonded to four Cu2+ atoms to form corner-sharing OCu4 trigonal pyramids. In the second O2- site, O2- is bonded to four Cu2+ atoms to form corner-sharing OCu4 trigonal pyramids. In the third O2- site, O2- is bonded in a distorted linear geometry to one Ba2+, one V5+, and one Cu2+ atom. In the fourth O2- site, O2- is bonded in a linear geometry to one V5+ and one Cu2+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one V5+ and two Cu2+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one V5+ and two Cu2+ atoms. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V5+ and three Cu2+ atoms. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V5+ and three Cu2+ atoms. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to one V5+ and two equivalent Cu2+ atoms. In the tenth O2- site, O2- is bonded in a 1-coordinate geometry to one V5+ and two equivalent Cu2+ atoms. In the eleventh O2- site, O2- is bonded to one Mg2+, one V5+, and two equivalent Cu2+ atoms to form distorted OMgVCu2 tetrahedra that share corners with two equivalent OCu4 trigonal pyramids and edges with two equivalent OMgVCu2 tetrahedra. In the twelfth O2- site, O2- is bonded to one Mg2+, one V5+, and two equivalent Cu2+ atoms to form OMgVCu2 tetrahedra that share corners with two equivalent OCu4 trigonal pyramids and edges with two equivalent OMgVCu2 tetrahedra. In the thirteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one V5+ and two Cu2+ atoms. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, one V5+, and two Cu2+ atoms. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Mg2+, and one V5+ atom. In the sixteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Mg2+, and one V5+ atom. In the seventeenth O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Mg2+, and one V5+ atom. In the eighteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Ba2+, one Mg2+, and one V5+ atom. In the nineteenth O2- site, O2- is bonded to one Mg2+, one V5+, and two Cu2+ atoms to form distorted OMgVCu2 tetrahedra that share a cornercorner with one OMgVCu2 tetrahedra, corners with two OCu4 trigonal pyramids, and edges with two OMgVCu2 tetrahedra. In the twentieth O2- site, O2- is bonded to one Mg2+, one V5+, and two Cu2+ atoms to form distorted OMgVCu2 tetrahedra that share a cornercorner with one OMgVCu2 tetrahedra, corners with two OCu4 trigonal pyramids, and edges with two OMgVCu2 tetrahedra.