Polarity of the water/octanol interface

Molecular dynamics computer simulations of a point dipole imbedded in a cavity at the water/octanol interface are used to compute the electronic absorption spectra of a chromophore as a function of its location at the interface. The model is capable of qualitatively accounting for the experimental observation of a low polarity alkane-like region at the interface. The molecular dynamics calculations suggest that this region is the result of a strong preferential orientation of hydrogen-bonded octanol molecules perpendicular to the interface.