2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/23146A Monte Carlo method is given to compute the binding affinity of a ligand to a protein. The method involves extending configuration space by a discrete variable indicating whether the ligand is bound to the protein and a special Monte Carlo move which allows transitions between the unbound and bound states. Provided that an accurate protein structure is given, that the protein-ligand binding site is known, and that an accurate chemical force field together with a continuum solvation model is used, this method provides a quantitative estimate of the free energy of binding.RevTex, 10 pages with 5 figures. Explanatory figure addedStatistical MechanicsBiological PhysicsChemical PhysicsQuantitative Methodstext