Dynamics of linear and branched alkane melts: Molecular dynamics test of theory for long time dynamics

摘要: Molecular dynamics (MD) simulations of united atom models for alkane melts are compared with a recently developed theory calculating the memory functions flexible polymers. The is based upon an approximate solution diffusion equation without hydrodynamic interactions. polymer described by using time correlation which expressed in terms set equilibrium averages and eigenvalues eigenfunctions operator. For enough chains sufficiently high molecular weight, interactions screened, simplified solvent model used expected to be adequate. only parameter not defined MD bead friction coefficient ζ. In limit weak (Rouse dynamics), ζ can determined from applying Rouse relation D=kT/NζR. Given this choice ζR, computed t...