Materials Data on KMg3V3CuO12 by Materials Project
KMg3V3CuO12 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.67–3.02 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, an edgeedge with one MgO6 octahedra, and an edgeedge with one MgO6 pentagonal pyramid. There are a spread of Mg–O bond distances ranging from 2.05–2.16 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 pentagonal pyramids that share corners with six VO4 tetrahedra and edges with two equivalent MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.13–2.18 Å. There are two inequivalent V5+ sites. In the first V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with four equivalent MgO6 octahedra and corners with two equivalent MgO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 35–64°. There are a spread of V–O bond distances ranging from 1.71–1.77 Å. In the second V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with four equivalent MgO6 octahedra and corners with two equivalent MgO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 59–61°. There is two shorter (1.75 Å) and two longer (1.76 Å) V–O bond length. Cu2+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.93 Å) and two longer (1.98 Å) Cu–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+, one Mg2+, and one V5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one V5+, and one Cu2+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, two Mg2+, and one V5+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+, one V5+, and one Cu2+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Mg2+ and one V5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, two Mg2+, and one V5+ atom.