AB-INITIO EVALUATION OF LOCAL EFFECTIVE INTERACTIONS IN α′ NAV2O5
Résumé
We compute by means of extensive quantum chemistry methods the nearest-neighbour effective exchange and hopping integrals for α‧ NaV2O5. We find that, unlike usually assumed, the system is basically a two-dimensional asymmetric triangular Heisenberg lattice, where the sites represent unpaired electrons delocalised on the VOV rungs.