C18H18CuN4O10, triclinic, P (1) over bar (no. 2), a = 7.2610(4) angstrom, b = 7.7534(6) angstrom, c = 9.5266(7) angstrom, alpha = 72.429(7)degrees, beta = 82.633(5)degrees, gamma = 72.083(6)degrees, V = 486.1 angstrom(3), z = 1, R-gt(F) = 0.032, wR(ref)(F-2) = 0.066, T = 296 K.