Atomistic Insight into the Host-Guest Interaction of a Photo-Responsive Metal-Organic Framework

Photo-responsive functional materials have gained increasing attention due to their externally tunable properties. Molecular switches embedded in these materials enable to control phenomena at the atomic level by light. Metal-Organic Frameworks (MOFs) provide a versatile platform to immobilize these photo-responsive units within defined molecular environments to optimize the intended functionality. For the application of these photo-responsive MOFs (pho-MOFs), it is crucial to understand the influence of the switching state on the host-guest interaction. Therefore, we present a detailed insight into the impact of molecular switching the intermolecular interaction. By performing atomistic simulations, we revealed that due to different interactions of the guest molecules with the two isomeric states of an azobenzene-functionalized MOF, both the adsorption sites and the orientation of the molecules within the pores are modulated. By shedding light on the host-guest interaction, our study highlights the unique potential of pho-MOFs to tailor molecular interaction by light.