InAlCuO4 is Aluminum carbonitride-derived structured and crystallizes in the trigonal R3m space group. Cu(1) is bonded to one O(2), one O(4), and three equivalent O(3) atoms to form distorted CuO5 trigonal bipyramids that share corners with three equivalent In(1)O6 octahedra, corners with six equivalent Cu(1)O5 trigonal bipyramids, and edges with three equivalent Al(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 62°. In(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form InO6 octahedra that share corners with three equivalent Cu(1)O5 trigonal bipyramids, corners with three equivalent Al(1)O5 trigonal bipyramids, and edges with six equivalent In(1)O6 octahedra. Al(1) is bonded to one O(1), one O(3), and three equivalent O(4) atoms to form AlO5 trigonal bipyramids that share corners with three equivalent In(1)O6 octahedra, corners with six equivalent Al(1)O5 trigonal bipyramids, and edges with three equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 59°. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent In(1) and one Al(1) atom to form distorted OAlIn3 trigonal pyramids that share  a cornercorner with one O(3)AlCu3 tetrahedra, corners with three equivalent O(2)In3Cu tetrahedra, corners with three equivalent O(4)Al3Cu trigonal pyramids, corners with six equivalent O(1)AlIn3 trigonal pyramids, and edges with three equivalent O(2)In3Cu tetrahedra. In the second O site, O(2) is bonded to one Cu(1) and three equivalent In(1) atoms to form OIn3Cu tetrahedra that share corners with three equivalent O(3)AlCu3 tetrahedra, corners with six equivalent O(2)In3Cu tetrahedra,  a cornercorner with one O(4)Al3Cu trigonal pyramid, corners with three equivalent O(1)AlIn3 trigonal pyramids, and edges with three equivalent O(1)AlIn3 trigonal pyramids. In the third O site, O(3) is bonded to three equivalent Cu(1) and one Al(1) atom to form OAlCu3 tetrahedra that share corners with three equivalent O(2)In3Cu tetrahedra, corners with six equivalent O(3)AlCu3 tetrahedra,  a cornercorner with one O(1)AlIn3 trigonal pyramid, and edges with three equivalent O(4)Al3Cu trigonal pyramids. In the fourth O site, O(4) is bonded to one Cu(1) and three equivalent Al(1) atoms to form OAl3Cu trigonal pyramids that share  a cornercorner with one O(2)In3Cu tetrahedra, corners with three equivalent O(1)AlIn3 trigonal pyramids, corners with six equivalent O(4)Al3Cu trigonal pyramids, and edges with three equivalent O(3)AlCu3 tetrahedra.
InAlCuO4 is Aluminum carbonitride-derived structured and crystallizes in the trigonal R3m space group. Cu(1) is bonded to one O(2), one O(4), and three equivalent O(3) atoms to form distorted CuO5 trigonal bipyramids that share corners with three equivalent In(1)O6 octahedra, corners with six equivalent Cu(1)O5 trigonal bipyramids, and edges with three equivalent Al(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 62°. The Cu(1)-O(2) bond length is 2.00 Å. The Cu(1)-O(4) bond length is 2.22 Å. All Cu(1)-O(3) bond lengths are 1.98 Å. In(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form InO6 octahedra that share corners with three equivalent Cu(1)O5 trigonal bipyramids, corners with three equivalent Al(1)O5 trigonal bipyramids, and edges with six equivalent In(1)O6 octahedra. All In(1)-O(1) bond lengths are 2.25 Å. All In(1)-O(2) bond lengths are 2.19 Å. Al(1) is bonded to one O(1), one O(3), and three equivalent O(4) atoms to form AlO5 trigonal bipyramids that share corners with three equivalent In(1)O6 octahedra, corners with six equivalent Al(1)O5 trigonal bipyramids, and edges with three equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 59°. The Al(1)-O(1) bond length is 1.84 Å. The Al(1)-O(3) bond length is 1.87 Å. All Al(1)-O(4) bond lengths are 1.94 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent In(1) and one Al(1) atom to form distorted OAlIn3 trigonal pyramids that share  a cornercorner with one O(3)AlCu3 tetrahedra, corners with three equivalent O(2)In3Cu tetrahedra, corners with three equivalent O(4)Al3Cu trigonal pyramids, corners with six equivalent O(1)AlIn3 trigonal pyramids, and edges with three equivalent O(2)In3Cu tetrahedra. In the second O site, O(2) is bonded to one Cu(1) and three equivalent In(1) atoms to form OIn3Cu tetrahedra that share corners with three equivalent O(3)AlCu3 tetrahedra, corners with six equivalent O(2)In3Cu tetrahedra,  a cornercorner with one O(4)Al3Cu trigonal pyramid, corners with three equivalent O(1)AlIn3 trigonal pyramids, and edges with three equivalent O(1)AlIn3 trigonal pyramids. In the third O site, O(3) is bonded to three equivalent Cu(1) and one Al(1) atom to form OAlCu3 tetrahedra that share corners with three equivalent O(2)In3Cu tetrahedra, corners with six equivalent O(3)AlCu3 tetrahedra,  a cornercorner with one O(1)AlIn3 trigonal pyramid, and edges with three equivalent O(4)Al3Cu trigonal pyramids. In the fourth O site, O(4) is bonded to one Cu(1) and three equivalent Al(1) atoms to form OAl3Cu trigonal pyramids that share  a cornercorner with one O(2)In3Cu tetrahedra, corners with three equivalent O(1)AlIn3 trigonal pyramids, corners with six equivalent O(4)Al3Cu trigonal pyramids, and edges with three equivalent O(3)AlCu3 tetrahedra.