From molecules to organic crystals: The contribution of quantum chemistry

Quantum chemistry is now able to provide a quantitative description of the topology of electron interactions in organic conductors. Beyond the one ele ctron picture, the calculation of Coulomb repulsion interactions is also fe asible. The refinement of the calculation tools now offers a deeper and con sistent insight on the intra and intermolecular interactions in the materia ls, that do not suffer from the preconceptions that have plagued the extrac tion of phenomenological model Hamiltonians. VB models form the backbone of consistent extraction procedures. They can also reveal sizeable new electr on coupling mechanisms such as: the anion-cation pole-induced dipole intera ction.