Non-covalent Interactions of CO₂ with Functional Groups of Metal-Organic Frameworks from a CCSD(T) Scheme Applicable to Large Systems.

The strength of interactions between CO2 and 23 building blocks of metal-organic frameworks are reported in this paper. This theoretical study is based on an incremental, explicitly correlated coupled-cluster scheme with interference effects. This scheme allows the accurate calculation of molecular complexes such as zinc acetate (32 non-hydrogen atoms) at the CCSD(T) level, close to the basis set limit. Higher CO2 affinity for complexes with nitrogen-containing heterocycles is predicted from the calculated interaction energies. The good agreement between the interaction energies obtained from the CCSD(T) scheme and DFT-D3 is discussed.