Materials Data on Al6Cu2B4O17 by Materials Project
Cu2Al6B4O17 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 trigonal bipyramids that share corners with two equivalent AlO6 octahedra, a cornercorner with one AlO5 trigonal bipyramid, edges with two equivalent AlO6 octahedra, an edgeedge with one CuO5 trigonal bipyramid, and an edgeedge with one AlO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 55°. There are a spread of Cu–O bond distances ranging from 1.91–2.28 Å. In the second Cu2+ site, Cu2+ is bonded to five O2- atoms to form distorted CuO5 trigonal bipyramids that share corners with two equivalent AlO6 octahedra, a cornercorner with one AlO5 trigonal bipyramid, edges with two equivalent AlO6 octahedra, an edgeedge with one CuO5 trigonal bipyramid, and an edgeedge with one AlO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 52°. There are a spread of Cu–O bond distances ranging from 1.88–2.22 Å. There are four inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one CuO5 trigonal bipyramid, a cornercorner with one AlO5 trigonal bipyramid, edges with two equivalent AlO6 octahedra, an edgeedge with one CuO5 trigonal bipyramid, and an edgeedge with one AlO5 trigonal bipyramid. There are a spread of Al–O bond distances ranging from 1.85–2.00 Å. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one CuO5 trigonal bipyramid, a cornercorner with one AlO5 trigonal bipyramid, edges with two equivalent AlO6 octahedra, an edgeedge with one CuO5 trigonal bipyramid, and an edgeedge with one AlO5 trigonal bipyramid. There are a spread of Al–O bond distances ranging from 1.85–1.99 Å. In the third Al3+ site, Al3+ is bonded to five O2- atoms to form AlO5 trigonal bipyramids that share corners with two equivalent AlO6 octahedra, a cornercorner with one CuO5 trigonal bipyramid, edges with two equivalent AlO6 octahedra, an edgeedge with one CuO5 trigonal bipyramid, and an edgeedge with one AlO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 50°. There are a spread of Al–O bond distances ranging from 1.79–2.02 Å. In the fourth Al3+ site, Al3+ is bonded to five O2- atoms to form AlO5 trigonal bipyramids that share corners with two equivalent AlO6 octahedra, a cornercorner with one CuO5 trigonal bipyramid, edges with two equivalent AlO6 octahedra, an edgeedge with one CuO5 trigonal bipyramid, and an edgeedge with one AlO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 51°. There are a spread of Al–O bond distances ranging from 1.80–1.91 Å. There are four inequivalent B3+ sites. In the first B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.36 Å) and two longer (1.40 Å) B–O bond length. In the second B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.37 Å) and one longer (1.39 Å) B–O bond length. In the third B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.37 Å) and one longer (1.39 Å) B–O bond length. In the fourth B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.37 Å) and two longer (1.40 Å) B–O bond length. There are thirteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Al3+ and one B3+ atom. In the second O2- site, O2- is bonded in a distorted T-shaped geometry to two equivalent Al3+ and one B3+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Al3+ and one B3+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Al3+ and one B3+ atom. In the fifth O2- site, O2- is bonded to two Cu2+ and two equivalent Al3+ atoms to form corner-sharing OAl2Cu2 trigonal pyramids. In the sixth O2- site, O2- is bonded to four Al3+ atoms to form corner-sharing OAl4 trigonal pyramids. In the seventh O2- site, O2- is bonded to one Cu2+ and three Al3+ atoms to form corner-sharing OAl3Cu trigonal pyramids. In the eighth O2- site, O2- is bonded to one Cu2+ and three Al3+ atoms to form corner-sharing OAl3Cu trigonal pyramids. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one B3+ atom. In the tenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Cu2+, one Al3+, and one B3+ atom. In the eleventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one B3+ atom. In the twelfth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Cu2+, one Al3+, and one B3+ atom. In the thirteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Cu2+ and two Al3+ atoms.