Calculation of the potential of mean force from nonequilibrium measurements via maximum likelihood estimators.

We present an approach to the estimate of the potential of mean force along a generic reaction coordinate based on maximum likelihood methods and path-ensemble averages in systems driven far from equilibrium. Following similar arguments, various free energy estimators can be recovered, all providing comparable computational accuracy. The method, applied to the unfolding process of the alpha -helix form of an alanine decapeptide, gives results in good agreement with thermodynamic integration.