  We present a systematic, top-down, thermodynamic parametrization scheme for
dissipative particle dynamics (DPD) using water-octanol partition coefficients,
supplemented by water-octanol phase equilibria and pure liquid phase density
data. We demonstrate the feasibility of computing the required partition
coefficients in DPD using brute-force simulation, within an adaptive
semi-automatic staged optimization scheme. We test the methodology by fitting
to experimental partition coefficient data for twenty one small molecules in
five classes comprising alcohols and poly-alcohols, amines, ethers and simple
aromatics, and alkanes (i.e. hexane). Finally, we illustrate the
transferability of a subset of the determined parameters by calculating the
critical micelle concentrations of selected alkyl ethoxylate surfactants, in
good agreement with reported experimental values.
