The physical and chemical properties of molecules are the result of their three-dimensional (3D) structure. Importantly, flexible molecules do not have a single 3D structure but rather adopt a Boltzmannweighted ensemble of different conformations . Therefore, computational approaches in disciplines like spectroscopy , medicinal chemistry , and stereoselective synthesis need to take the conformational flexibility into account to provide accurate predictions. This, in turn, means that the accurate but fast prediction of conformational ensembles has long been appreciated as one of the prime objectives and challenges of computational chemistry.