Solvent effects on electronic spectra at liquid interfaces. A continuum electrostatic model

The electronic absorption line shape of a model chromophore at liquid inter faces is numerically evaluated using electrostatic continuum theory. The in terface is described as a sharp boundary separating two bulk media, each ch aracterized by different optical and static dielectric constant. The chromo phore is modeled as a pair of spherical cavities in which two equal and opp osite point charges are embedded, but more complicated charge distributions are possible. All possible orientations of the two cavities relative to th e interface are properly weighted, including the cases where each cavity ma y be located in both phases. Comparisons are made with experiments, approxi mate analytical results, and molecular dynamics simulations.