Abstract
The multiple scattering Xα method applied to an embedded CuCl5−6 cluster is used to describe the electronic structure of Cu+ in NaCl. Several calculations have been performed with different Cu–Cl distances in order to reach the equilibrium distance. The harmonic force constant of the vibrational breathing deformation of the cluster, deduced from the total energy curve vs the bond distance is in large agreement with experimental results, while the equilibrium distance is predicted slightly larger than the NaCl bulk value.