All-electron spin polarized DFT calculations have been performed to optimize the pentagonal bipyramidal (D-5h) geometry of the Cu-7 cluster by using the B3LYP and the B3PW1 functionals with different basis sets. Dirac scattered-wave and its non-relativistic limit calculations are used to calculate the Cu-63 hyperfine coupling constants using a first order perturbational procedure. Our calculations for the Cu-7 cluster predict the (2)A(2)" as its ground state. The calculated hyperfine coupling constants are in reasonable agreement with those experimentally determined for Cu-7 in a matrix isolated ESR study by Van Zee and Weltner. (C) 2004 Elsevier B.V. All rights reserved.