Li2Fe3CuO8 is Spinel-derived structured and crystallizes in the trigonal R-3m space group. Li(1) is bonded to one O(1) and three equivalent O(2) atoms to form LiO4 tetrahedra that share corners with three equivalent Cu(1)O6 octahedra and corners with nine equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-59°. Fe(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form FeO6 octahedra that share corners with six equivalent Li(1)O4 tetrahedra, edges with two equivalent Cu(1)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. Cu(1) is bonded to six equivalent O(2) atoms to form CuO6 octahedra that share corners with six equivalent Li(1)O4 tetrahedra and edges with six equivalent Fe(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Li(1) and three equivalent Fe(1) atoms to form distorted OLiFe3 trigonal pyramids that share corners with three equivalent O(1)LiFe3 trigonal pyramids, corners with nine equivalent O(2)LiFe2Cu trigonal pyramids, and edges with three equivalent O(2)LiFe2Cu trigonal pyramids. In the second O site, O(2) is bonded to one Li(1), two equivalent Fe(1), and one Cu(1) atom to form distorted OLiFe2Cu trigonal pyramids that share corners with three equivalent O(1)LiFe3 trigonal pyramids, corners with nine equivalent O(2)LiFe2Cu trigonal pyramids,  an edgeedge with one O(1)LiFe3 trigonal pyramid, and edges with two equivalent O(2)LiFe2Cu trigonal pyramids.
Li2Fe3CuO8 is Spinel-derived structured and crystallizes in the trigonal R-3m space group. Li(1) is bonded to one O(1) and three equivalent O(2) atoms to form LiO4 tetrahedra that share corners with three equivalent Cu(1)O6 octahedra and corners with nine equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-59°. The Li(1)-O(1) bond length is 1.96 Å. All Li(1)-O(2) bond lengths are 2.00 Å. Fe(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form FeO6 octahedra that share corners with six equivalent Li(1)O4 tetrahedra, edges with two equivalent Cu(1)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. Both Fe(1)-O(1) bond lengths are 2.01 Å. All Fe(1)-O(2) bond lengths are 2.02 Å. Cu(1) is bonded to six equivalent O(2) atoms to form CuO6 octahedra that share corners with six equivalent Li(1)O4 tetrahedra and edges with six equivalent Fe(1)O6 octahedra. All Cu(1)-O(2) bond lengths are 1.98 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Li(1) and three equivalent Fe(1) atoms to form distorted OLiFe3 trigonal pyramids that share corners with three equivalent O(1)LiFe3 trigonal pyramids, corners with nine equivalent O(2)LiFe2Cu trigonal pyramids, and edges with three equivalent O(2)LiFe2Cu trigonal pyramids. In the second O site, O(2) is bonded to one Li(1), two equivalent Fe(1), and one Cu(1) atom to form distorted OLiFe2Cu trigonal pyramids that share corners with three equivalent O(1)LiFe3 trigonal pyramids, corners with nine equivalent O(2)LiFe2Cu trigonal pyramids,  an edgeedge with one O(1)LiFe3 trigonal pyramid, and edges with two equivalent O(2)LiFe2Cu trigonal pyramids.