Insights into the Adsorption of Water and Small Alcohols on the Open-Metal Sites of Cu-BTC via Molecular Simulation

We report a computational study of water and small alcohols on coordinatively unsaturated sites in the CuBTC metalorganic framework using Monte Carlo simulations. Binding energies and characteristic distances with copper centers are in agreement with these obtained from experiments and theoretical methods revealing the reliability of the classical force fields to describe the microscopic behavior. We rationalized the adsorption isotherms in terms of copper solvation and molecular association. Although water goes to all copper centers more rapidly than alcohols, the earlier nucleation via hydrogen bonds of alcohols explains their larger loading at the dilute regime.