Optimized monopole expansions for the representation of the electrostatic properties of the nucleic acids

Optimized monopole expansions for the subunits of the nucleic acids are developed by a reparametrizatio of the Hückel–Del Re procedure designed to reproduce closely the electrostatic properties obtained with precise overlap multipole expansions. It is shown that satisfactory values of both potential and field may be obtained for different DNA conformations and for a transfer RNA. The charge redistribution occuring between the subunits upon forming the nucleic acids is also investigated by ab initio calculations and accounted for in developing the new parametrization.