Oligomers of poly(ethylene oxide): Molecular dynamics with a polarizable force field

A semi-empirical force-field for simulating oligomers of poly(ethylene oxide) is developed with the united atom representation for methyl and methylene groups. Polarizability of groups is mimicked by polarizable finite dipoles. The force field parameters are adjusted using both empirical data (density, dipole moments, dielectric constant) and ab initio calculations (dihedral torsion potentials, conformation energies). The molecular dynamics simulations make use of a novel predictor-corrector scheme for the self-consistent field, allowing only one evaluation of forces per integration step. Focus is on quantities related to ionic motion (dielectric constant and viscosity), the gauche effect, and methodology of simulations of complex polarizable molecules.