title: A novel density functional study of the ground state properties of a localized trinuclear copper(II,II,III) mixed-valence system.
abstract: Herein we report the analysis of a mixed-valence localized trinuclear copper(II,II,III) cluster by density functional theory. We focused on two peculiar aspects of this system. First we investigated the triplet ground state potential energy surface on a model system. To this end we computed, on the [E multiply sign in circle e] adiabatic potential energy surface, the potential energy profile along the e mode and constructed ab initio the full potential energy surface (the so called Mexican hat), by a fitting procedure. Next, we analyzed the magnetooptical properties of the minimum energy structures. In particular, we applied the single determinant method to compute the full manifold of states arising from the highest occupied molecular orbitals (magnetic orbitals). This procedure yielded results in agreement with previous calculations and with the available experimental data when using a model closer to the X-ray structure or when directly dealing with the complete structure of the system.