LAUSR

Flexible metal–organic frameworks (MOFs) are characterized by their responsiveness to guest adsorption, which is called ‘gate opening’ or ‘breathing’. Free energy calculations are tools for evaluating the stability of these systems, and are crucial for understanding the adsorption-induced deformation of flexible MOFs. Herein, we highlight the recent progress in free energy calculations for the gate-opening and breathing behavior of flexible MOFs. Recently, a thermodynamic approach was proposed to predict the framework flexibility of MOFs against eternal stimuli in a generic way. This method is based on free energy calculations with the so-called thermodynamic integration method using molecular simulations, which may open up the possibility of in silico anticipation of gas storage and/or separation abilities of flexible MOFs.