Static polarizability surfaces of the van der Waals complex CH4-N2.

The static polarizability surfaces of the van der Waals complex CH(4)-N(2) have been calculated for a broad range of intermolecular separations and configurations in the approximation of rigid interacting molecules. The calculations have been carried out at the CCSD(T) and MP2 levels of the theory using the aug-cc-pVTZ basis set with the BSSE correction and within the framework of the classical long-range multipolar induction and dispersion interactions. It was shown that the results of analytical polarizability calculations for the CH(4)-N(2) complex are in a good agreement with the ab initio polarizabilities in the outer part of the van der Waals well on the complex potential surface. Ab initio calculations of the polarizability tensor invariants for the complex being in the most stable configurations were carried out. The change in the polarizability of CH(4)-N(2) due to the deformation of the CH(4) and N(2) monomers at the formation of the complex was estimated. In the framework of the analytical approach the polarizability functions alpha(ii)(R) of the free oriented interacting molecules CH(4) and N(2) were calculated.