A large gap exists between bulk, continuum models of dielectric polarization and atomistic molecular models. This gap stands in the way of building density-based multiscale simulations. The present state of theory is such that spectra can be obtained from either a single molecule or a whole periodic simulation cell. Although the single-molecule case converges quickly, it neglects certain intermolecular correlations. The whole-cell case has the opposite difficulty of finding all correlations, but with deteriorating convergence as the system size increases. A new examination of the Green-Kubo relations shows how to take advantage of both limits, greatly increasing convergence of dielectric response functions in inhomogeneous, nanoscale environments. The result is constructive, and is illustrated by computing local dielectrics from molecular dynamics.

Applying the fluctuation-dissipation theorem to compute local dielectric properties

247th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.