We investigate theoretically the structure and electronic properties o
f the interface between aluminum and polyaniline in order to obtain in
formation on the most favored adsorption sites and the nature of the i
nteractions occurring between the metal and the polymer surface. For t
his purpose, quantum chemical calculations are performed on model syst
ems consisting of short-chain model molecules interacting with two met
al atoms. We use both an ab initio Hartree-Fock Hamiltonian with an ex
tended basis set and the MNDO semiempirical technique to study the com
plex between two Al atoms and p-phenylenediamine, a model molecule for
leucoemeraldine base. The formation of stable complexes between two A
l atoms and the molecules induce strong geometric modifications along
the organic backbone: electron charge transfer takes place from the me
tal atom to the organic system and the pi electronic levels are strong
ly perturbed.