(73f) Studying Inhomogeneous Ion-Containing Complex Fluids Using Polarizable Field-Theoretic Simulations

Delaney, K., University of California, Santa Barbara
Fredrickson, G. H., University of California, Santa Barbara
The growing interest in ion-containing polymeric materials with heterogeneous dielectric properties (salt-doped polymers, polyelectrolytes, ionomers, polymeric ionic liquids, etc.) has motivated the recent development of an equilibrium polarizable field theory, in which molecules are constructed out of beads that are granted polarizability via attached classical Drude oscillators. The incorporation of bead polarizabilities has the advantage that it self-consistently embeds dielectric response, van der Waals interactions and ion solvation energies into the theory, yet simulations of complex fluids based on such molecular models are rarely attempted. Here, by casting the statistical theory into field-theoretic form, it can be simulated without approximation using the complex Langevin field-theoretic simulation (CL-FTS) approach. This is crucial, since much of the emergent charge physics vanishes in the absence of electrostatic field fluctuations, rendering the mean-field approximation to the polarizable field theory inappropriate for most problems of interest. In this talk, I will summarize my recent work in applying the polarizable field theory to study i) the phase behavior of neat and salt-doped polymeric systems, and ii) the dielectric response of electrolyte solutions. This work reveals important aspects of the physics of ion-containing polarizable fluids which have not been previously anticipated in the literature.