Unveiling the mechanism of selective gate-driven diffusion of CO2 over N2 in MFU-4 metal–organic framework

The metal–organic framework MFU-4 shows preferential adsorption of CO2 over N2. This cannot be explained in terms of pore size only. Computational modelling suggests that the unique structure and flexibility of its small 8Cl-cube pore shows a unique gate-diffusion behaviour with different responses to CO2 and N2.