Abstract
We introduced a method a method for analyze three dimensional distributions of electro static potentials and forces in a DNA molecule. A DNA molecule was expressed by a three layers cylinder so as to reflect the Debye-Huckel theory. The potential in each region was described by Laplace and Poisson equations. The Green function method was applied for the discrete helical charge distribution within a one helical turn of the finite cylinder. The calculated potentials and forces depended on the circumferential angles. The Present method, when it was improved, will be available for evaluating the free energy of the DNA molecule.
