To calculate the residence time, we adopt the iMetaD approach. At odds with the original metadynamics, the purpose of iMetaD is not the calculation of the full free-energy profile of the binding process (which involves sampling both the binding and unbinding processes). Instead, it focuses on properly reweighting the simulation time for the unbinding process. When minimal bias is deposited on the transition state, the metadynamics bias can be used to compute the unbiased residence time τ for each run