U3Cu2S7 crystallizes in the hexagonal P6_3 space group. U(1) is bonded in a 8-coordinate geometry to one S(1), three equivalent S(2), and four equivalent S(3) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a tetrahedral geometry to one S(1) and three equivalent S(2) atoms. In the second Cu site, Cu(2) is bonded in a trigonal planar geometry to three equivalent S(3) atoms. There are three inequivalent S sites. In the first S site, S(1) is bonded in a tetrahedral geometry to three equivalent U(1) and one Cu(1) atom. In the second S site, S(2) is bonded in a 4-coordinate geometry to three equivalent U(1) and one Cu(1) atom. In the third S site, S(3) is bonded in a 5-coordinate geometry to four equivalent U(1) and one Cu(2) atom.
U3Cu2S7 crystallizes in the hexagonal P6_3 space group. U(1) is bonded in a 8-coordinate geometry to one S(1), three equivalent S(2), and four equivalent S(3) atoms. The U(1)-S(1) bond length is 2.76 Å. There are a spread of U(1)-S(2) bond distances ranging from 2.65-2.96 Å. There are a spread of U(1)-S(3) bond distances ranging from 2.82-3.17 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a tetrahedral geometry to one S(1) and three equivalent S(2) atoms. The Cu(1)-S(1) bond length is 2.26 Å. All Cu(1)-S(2) bond lengths are 2.26 Å. In the second Cu site, Cu(2) is bonded in a trigonal planar geometry to three equivalent S(3) atoms. All Cu(2)-S(3) bond lengths are 2.19 Å. There are three inequivalent S sites. In the first S site, S(1) is bonded in a tetrahedral geometry to three equivalent U(1) and one Cu(1) atom. In the second S site, S(2) is bonded in a 4-coordinate geometry to three equivalent U(1) and one Cu(1) atom. In the third S site, S(3) is bonded in a 5-coordinate geometry to four equivalent U(1) and one Cu(2) atom.