Co4CuAl12 crystallizes in the monoclinic C2/m space group. There are five inequivalent Co sites. In the first Co site, Co(1) is bonded in a 9-coordinate geometry to one Cu(1), one Al(1), one Al(11), one Al(12), one Al(13), one Al(2), one Al(3), one Al(4), and one Al(5) atom. In the second Co site, Co(2) is bonded in a 8-coordinate geometry to one Al(10), one Al(9), two equivalent Al(1), two equivalent Al(11), and two equivalent Al(4) atoms. In the third Co site, Co(3) is bonded in a 10-coordinate geometry to one Cu(1), one Al(8), two equivalent Al(2), two equivalent Al(3), two equivalent Al(6), and two equivalent Al(9) atoms. In the fourth Co site, Co(4) is bonded in a 10-coordinate geometry to one Al(12), one Al(8), two equivalent Al(2), two equivalent Al(3), two equivalent Al(6), and two equivalent Al(7) atoms. In the fifth Co site, Co(5) is bonded in a 10-coordinate geometry to one Cu(2), one Al(10), one Al(12), one Al(7), two equivalent Al(1), two equivalent Al(4), and two equivalent Al(5) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 10-coordinate geometry to one Co(3), two equivalent Co(1), one Al(11), one Al(8), one Al(9), two equivalent Al(3), and two equivalent Al(4) atoms. In the second Cu site, Cu(2) is bonded in a distorted cuboctahedral geometry to two equivalent Co(5), two equivalent Al(13), four equivalent Al(4), and four equivalent Al(5) atoms. There are thirteen inequivalent Al sites. In the first Al site, Al(1) is bonded in a 3-coordinate geometry to one Co(1), one Co(2), one Co(5), and one Al(12) atom. In the second Al site, Al(2) is bonded in a 2-coordinate geometry to one Co(1), one Co(3), one Co(4), one Al(12), and two equivalent Al(3) atoms. In the third Al site, Al(3) is bonded in a 12-coordinate geometry to one Co(1), one Co(3), one Co(4), one Cu(1), one Al(13), one Al(4), one Al(6), one Al(7), two equivalent Al(2), and two equivalent Al(8) atoms. In the fourth Al site, Al(4) is bonded in a 5-coordinate geometry to one Co(1), one Co(2), one Co(5), one Cu(1), one Cu(2), one Al(11), and one Al(3) atom. In the fifth Al site, Al(5) is bonded in a 3-coordinate geometry to one Co(1), one Co(5), one Cu(2), and one Al(11) atom. In the sixth Al site, Al(6) is bonded in a 4-coordinate geometry to two equivalent Co(3), two equivalent Co(4), and two equivalent Al(3) atoms. In the seventh Al site, Al(7) is bonded in a 3-coordinate geometry to one Co(5), two equivalent Co(4), one Al(12), and two equivalent Al(3) atoms. In the eighth Al site, Al(8) is bonded in a 3-coordinate geometry to one Co(3), one Co(4), one Cu(1), one Al(12), and four equivalent Al(3) atoms. In the ninth Al site, Al(9) is bonded in a 4-coordinate geometry to one Co(2), two equivalent Co(3), and one Cu(1) atom. In the tenth Al site, Al(10) is bonded in a distorted linear geometry to one Co(2), one Co(5), one Al(11), and one Al(12) atom. In the eleventh Al site, Al(11) is bonded in a 11-coordinate geometry to two equivalent Co(1), two equivalent Co(2), one Cu(1), one Al(10), one Al(11), two equivalent Al(4), and two equivalent Al(5) atoms. In the twelfth Al site, Al(12) is bonded in a 11-coordinate geometry to one Co(4), one Co(5), two equivalent Co(1), one Al(10), one Al(7), one Al(8), two equivalent Al(1), and two equivalent Al(2) atoms. In the thirteenth Al site, Al(13) is bonded in a distorted linear geometry to two equivalent Co(1), one Cu(2), and two equivalent Al(3) atoms.
Co4CuAl12 crystallizes in the monoclinic C2/m space group. There are five inequivalent Co sites. In the first Co site, Co(1) is bonded in a 9-coordinate geometry to one Cu(1), one Al(1), one Al(11), one Al(12), one Al(13), one Al(2), one Al(3), one Al(4), and one Al(5) atom. The Co(1)-Cu(1) bond length is 2.53 Å. The Co(1)-Al(1) bond length is 2.46 Å. The Co(1)-Al(11) bond length is 2.57 Å. The Co(1)-Al(12) bond length is 2.43 Å. The Co(1)-Al(13) bond length is 2.26 Å. The Co(1)-Al(2) bond length is 2.42 Å. The Co(1)-Al(3) bond length is 2.49 Å. The Co(1)-Al(4) bond length is 2.54 Å. The Co(1)-Al(5) bond length is 2.39 Å. In the second Co site, Co(2) is bonded in a 8-coordinate geometry to one Al(10), one Al(9), two equivalent Al(1), two equivalent Al(11), and two equivalent Al(4) atoms. The Co(2)-Al(10) bond length is 2.39 Å. The Co(2)-Al(9) bond length is 2.53 Å. Both Co(2)-Al(1) bond lengths are 2.43 Å. There is one shorter (2.48 Å) and one longer (2.55 Å) Co(2)-Al(11) bond length. Both Co(2)-Al(4) bond lengths are 2.53 Å. In the third Co site, Co(3) is bonded in a 10-coordinate geometry to one Cu(1), one Al(8), two equivalent Al(2), two equivalent Al(3), two equivalent Al(6), and two equivalent Al(9) atoms. The Co(3)-Cu(1) bond length is 2.55 Å. The Co(3)-Al(8) bond length is 2.39 Å. Both Co(3)-Al(2) bond lengths are 2.39 Å. Both Co(3)-Al(3) bond lengths are 2.70 Å. Both Co(3)-Al(6) bond lengths are 2.44 Å. There is one shorter (2.42 Å) and one longer (2.55 Å) Co(3)-Al(9) bond length. In the fourth Co site, Co(4) is bonded in a 10-coordinate geometry to one Al(12), one Al(8), two equivalent Al(2), two equivalent Al(3), two equivalent Al(6), and two equivalent Al(7) atoms. The Co(4)-Al(12) bond length is 2.57 Å. The Co(4)-Al(8) bond length is 2.37 Å. Both Co(4)-Al(2) bond lengths are 2.70 Å. Both Co(4)-Al(3) bond lengths are 2.49 Å. Both Co(4)-Al(6) bond lengths are 2.46 Å. There is one shorter (2.43 Å) and one longer (2.51 Å) Co(4)-Al(7) bond length. In the fifth Co site, Co(5) is bonded in a 10-coordinate geometry to one Cu(2), one Al(10), one Al(12), one Al(7), two equivalent Al(1), two equivalent Al(4), and two equivalent Al(5) atoms. The Co(5)-Cu(2) bond length is 2.56 Å. The Co(5)-Al(10) bond length is 2.36 Å. The Co(5)-Al(12) bond length is 2.56 Å. The Co(5)-Al(7) bond length is 2.39 Å. Both Co(5)-Al(1) bond lengths are 2.62 Å. Both Co(5)-Al(4) bond lengths are 2.45 Å. Both Co(5)-Al(5) bond lengths are 2.43 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 10-coordinate geometry to one Co(3), two equivalent Co(1), one Al(11), one Al(8), one Al(9), two equivalent Al(3), and two equivalent Al(4) atoms. The Cu(1)-Al(11) bond length is 2.38 Å. The Cu(1)-Al(8) bond length is 2.56 Å. The Cu(1)-Al(9) bond length is 2.38 Å. Both Cu(1)-Al(3) bond lengths are 2.52 Å. Both Cu(1)-Al(4) bond lengths are 2.61 Å. In the second Cu site, Cu(2) is bonded in a distorted cuboctahedral geometry to two equivalent Co(5), two equivalent Al(13), four equivalent Al(4), and four equivalent Al(5) atoms. Both Cu(2)-Al(13) bond lengths are 3.01 Å. All Cu(2)-Al(4) bond lengths are 2.79 Å. All Cu(2)-Al(5) bond lengths are 2.53 Å. There are thirteen inequivalent Al sites. In the first Al site, Al(1) is bonded in a 3-coordinate geometry to one Co(1), one Co(2), one Co(5), and one Al(12) atom. The Al(1)-Al(12) bond length is 2.67 Å. In the second Al site, Al(2) is bonded in a 2-coordinate geometry to one Co(1), one Co(3), one Co(4), one Al(12), and two equivalent Al(3) atoms. The Al(2)-Al(12) bond length is 2.66 Å. There is one shorter (2.66 Å) and one longer (2.82 Å) Al(2)-Al(3) bond length. In the third Al site, Al(3) is bonded in a 12-coordinate geometry to one Co(1), one Co(3), one Co(4), one Cu(1), one Al(13), one Al(4), one Al(6), one Al(7), two equivalent Al(2), and two equivalent Al(8) atoms. The Al(3)-Al(13) bond length is 2.92 Å. The Al(3)-Al(4) bond length is 2.71 Å. The Al(3)-Al(6) bond length is 2.71 Å. The Al(3)-Al(7) bond length is 2.78 Å. There is one shorter (2.72 Å) and one longer (2.89 Å) Al(3)-Al(8) bond length. In the fourth Al site, Al(4) is bonded in a 5-coordinate geometry to one Co(1), one Co(2), one Co(5), one Cu(1), one Cu(2), one Al(11), and one Al(3) atom. The Al(4)-Al(11) bond length is 2.69 Å. In the fifth Al site, Al(5) is bonded in a 3-coordinate geometry to one Co(1), one Co(5), one Cu(2), and one Al(11) atom. The Al(5)-Al(11) bond length is 2.68 Å. In the sixth Al site, Al(6) is bonded in a 4-coordinate geometry to two equivalent Co(3), two equivalent Co(4), and two equivalent Al(3) atoms. In the seventh Al site, Al(7) is bonded in a 3-coordinate geometry to one Co(5), two equivalent Co(4), one Al(12), and two equivalent Al(3) atoms. The Al(7)-Al(12) bond length is 2.57 Å. In the eighth Al site, Al(8) is bonded in a 3-coordinate geometry to one Co(3), one Co(4), one Cu(1), one Al(12), and four equivalent Al(3) atoms. The Al(8)-Al(12) bond length is 2.75 Å. In the ninth Al site, Al(9) is bonded in a 4-coordinate geometry to one Co(2), two equivalent Co(3), and one Cu(1) atom. In the tenth Al site, Al(10) is bonded in a distorted linear geometry to one Co(2), one Co(5), one Al(11), and one Al(12) atom. The Al(10)-Al(11) bond length is 2.68 Å. The Al(10)-Al(12) bond length is 2.72 Å. In the eleventh Al site, Al(11) is bonded in a 11-coordinate geometry to two equivalent Co(1), two equivalent Co(2), one Cu(1), one Al(10), one Al(11), two equivalent Al(4), and two equivalent Al(5) atoms. The Al(11)-Al(11) bond length is 2.60 Å. In the twelfth Al site, Al(12) is bonded in a 11-coordinate geometry to one Co(4), one Co(5), two equivalent Co(1), one Al(10), one Al(7), one Al(8), two equivalent Al(1), and two equivalent Al(2) atoms. In the thirteenth Al site, Al(13) is bonded in a distorted linear geometry to two equivalent Co(1), one Cu(2), and two equivalent Al(3) atoms.