Résumé
Soft porous crystals undergo large structural transformations under a variety of physical stimuli. Breathing-like transformations, occurring with a large volume change, have been associated with an existence of bi-stable or multi-stable crystal structures. Here, we provide a detailed, multiscale qualitative and quantitative analysis of the adsorption-induced “breathing” transformations in two metal organic frameworks (MOFs): MIL-53(Al) which is a reference case of our approach, and recently synthetized JUK-8, which does not show any bistability without adsorbate. The proposed approach is based on atomistic simulations and does not require any empirical or adjustable parameters. It allows for a prediction of potential structural transformations in MOF and, in the case of adsorption-induced deformations, a calculation of the adsorption stress. We also show that the quantitative agreement between calculated and experimental results critically depends on the quality of the dispersion energy correction.