DOE OSTI2020
In2Cu2O5 crystallizes in the monoclinic P2 space group. The structure is three-dimensional. there are four inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Cu–O bond distances ranging from 1.96–2.67 Å. In the second Cu2+ site, Cu2+ is bonded to five O2- atoms to form distorted CuO5 trigonal bipyramids that share corners with three InO6 octahedra, corners with four equivalent CuO5 trigonal bipyramids, edges with four equivalent InO6 octahedra, and an edgeedge with one CuO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 41–63°. There are a spread of Cu–O bond distances ranging from 1.96–2.62 Å. In the third Cu2+ site, Cu2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Cu–O bond distances ranging from 1.95–2.68 Å. In the fourth Cu2+ site, Cu2+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of Cu–O bond distances ranging from 1.95–2.70 Å. There are four inequivalent In3+ sites. In the first In3+ site, In3+ is bonded to six O2- atoms to form distorted InO6 octahedra that share corners with five InO6 octahedra, edges with two equivalent InO6 octahedra, and edges with four equivalent CuO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 15–65°. There are a spread of In–O bond distances ranging from 2.17–2.28 Å. In the second In3+ site, In3+ is bonded to six O2- atoms to form InO6 octahedra that share corners with five InO6 octahedra, corners with two equivalent CuO5 trigonal bipyramids, and edges with two equivalent InO6 octahedra. The corner-sharing octahedra tilt angles range from 16–65°. There are a spread of In–O bond distances ranging from 2.17–2.28 Å. In the third In3+ site, In3+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing InO6 octahedra. The corner-sharing octahedra tilt angles range from 16–65°. There are a spread of In–O bond distances ranging from 2.16–2.28 Å. In the fourth In3+ site, In3+ is bonded to six O2- atoms to form InO6 octahedra that share corners with five InO6 octahedra, a cornercorner with one CuO5 trigonal bipyramid, and edges with two equivalent InO6 octahedra. The corner-sharing octahedra tilt angles range from 18–65°. There are a spread of In–O bond distances ranging from 2.17–2.29 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to four equivalent Cu2+ and two equivalent In3+ atoms. In the second O2- site, O2- is bonded to two Cu2+ and two equivalent In3+ atoms to form distorted OIn2Cu2 trigonal pyramids that share corners with six OIn3Cu tetrahedra, corners with two equivalent OIn2Cu2 trigonal pyramids, an edgeedge with one OIn3Cu tetrahedra, and an edgeedge with one OIn2Cu2 trigonal pyramid. In the third O2- site, O2- is bonded to one Cu2+ and three In3+ atoms to form distorted OIn3Cu tetrahedra that share corners with six OIn3Cu tetrahedra, corners with six OIn2Cu2 trigonal pyramids, and an edgeedge with one OIn2Cu2 trigonal pyramid. In the fourth O2- site, O2- is bonded to two Cu2+ and two equivalent In3+ atoms to form distorted OIn2Cu2 trigonal pyramids that share corners with six OIn3Cu tetrahedra, corners with two equivalent OIn2Cu2 trigonal pyramids, an edgeedge with one OIn3Cu tetrahedra, and an edgeedge with one OIn2Cu2 trigonal pyramid. In the fifth O2- site, O2- is bonded to one Cu2+ and three In3+ atoms to form distorted OIn3Cu tetrahedra that share corners with six OIn3Cu tetrahedra, corners with six OIn2Cu2 trigonal pyramids, and an edgeedge with one OIn2Cu2 trigonal pyramid. In the sixth O2- site, O2- is bonded to two Cu2+ and two equivalent In3+ atoms to form distorted OIn2Cu2 trigonal pyramids that share corners with six OIn3Cu tetrahedra, corners with two equivalent OIn2Cu2 trigonal pyramids, an edgeedge with one OIn3Cu tetrahedra, and an edgeedge with one OIn2Cu2 trigonal pyramid. In the seventh O2- site, O2- is bonded to two Cu2+ and two equivalent In3+ atoms to form distorted OIn2Cu2 trigonal pyramids that share corners with six OIn3Cu tetrahedra, corners with two equivalent OIn2Cu2 trigonal pyramids, an edgeedge with one OIn3Cu tetrahedra, and an edgeedge with one OIn2Cu2 trigonal pyramid. In the eighth O2- site, O2- is bonded in a 6-coordinate geometry to four equivalent Cu2+ and two equivalent In3+ atoms. In the ninth O2- site, O2- is bonded to one Cu2+ and three In3+ atoms to form distorted OIn3Cu tetrahedra that share corners with six OIn3Cu tetrahedra, corners with six OIn2Cu2 trigonal pyramids, and an edgeedge with one OIn2Cu2 trigonal pyramid. In the tenth O2- site, O2- is bonded in a 6-coordinate geometry to four equivalent Cu2+ and two equivalent In3+ atoms. In the eleventh O2- site, O2- is bonded in a 6-coordinate geometry to four equivalent Cu2+ and two equivalent In3+ atoms. In the twelfth O2- site, O2- is bonded to one Cu2+ and three In3+ atoms to form distorted OIn3Cu tetrahedra that share corners with six OIn3Cu tetrahedra, corners with six OIn2Cu2 trigonal pyramids, and an edgeedge with one OIn2Cu2 trigonal pyramid.