Building on these ideas, we first develop two methodologies to evaluate the populations of non-bonded aggregates-one based on the analysis of MD trajectories and the other on conformational searches followed by a statistical thermodynamic treatment using model potential energy surfaces-and subsequently assess their accuracy by simulating the IR spectrum, focusing on the O H stretching region. Our methodologies are applied to phenol/carbon tetrachloride mixtures, which presents marked changes in the O H IR band with concentration. In these mixtures, phenol monomers coexist with various aggregates, whose distinct peaks in the 3000-3800 cm -1 range reflect the structure and conformational landscape of the system 58 . Self-association of phenol in CCl 4 indeed remains a challenging problem and, despite extensive experimental studies over the past decades , no general consensus exists regarding the degree of aggregation or the structures of the resulting clusters.