Self-consistent-field iterative transfer perturbation method and its application to the interaction between a polymer and a small molecule

An iterative transfer perturbation method is proposed to treat the interaction between a polymer and a small molecule at the level of the ab initio method. The validity of our method is examined by applying it to a simple model system and comparing the results with those from the conventional tight-binding SCF crystal orbital method. The interaction energies and charge distributions obtained are in excellent agreement between the two methods. The present perturbational approach is promising for application to the more complicated interaction between a polymer and impurities.