The Natural Charge – Natural Charge Flux – Overlap model: a modification of the charge-charge flux-overlap model through NPA charges

Abstract

Some models were developed for the interpretation of infrared intensities based on the distribution of molecular charge and its mobility during atomic displacement. The objective of this paper is to apply NPA charges in the C-CF-O model to obtain the dipole moment derivatives and infrared intensities of AH3, X2CY and some linear molecules. In all cases analyzed, the NC-NCF-O model was more accurate than the reference model Charge – Charge Flux – Dipole Flux (C–CF–DF). Furthermore, the computational cost of obtaining NPA charges and their respective flux are much lower than those obtained by more complex models. This allows a greater application for large molecules.