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 an d methylene groups. Polarizability of groups is mimicked by polarizabl e finite dipoles. The force field parameters are adjusted using both e mpirical data (density, dipole moments, dielectric constant) and ab in itio calculations (dihedral torsion potentials, conformation energies) . The molecular dynamics simulations make use of a novel predictor-cor rector scheme for the self-consistent field, allowing only one evaluat ion of forces per integration step. Focus is on quantities related to ionic motion (dielectric constant and viscosity), the gauche effect, a nd methodology of simulations of complex polarizable molecules.