The task to sort molecules can be quite challenging if they are very similar. This is even more the case if you want to sort a single molecular species according to its three-dimensional structure. The problem is that for most molecules a number of these so-called conformers are present and that they easily interconvert at room temperature. In a new study we propose how such a sorting can be achieved with molecular interference. We show how internally cold beams populated with just a single structure can be prepared. These might open new vistas for structure-sensitive collision studies. More information can be found here.

All four structures show the same molecule, they only differ in the three-dimensional arrangement. With our method we can make sure that both first diffraction orders (±1) are populated only with the red conformer, while it is a mixture of all four conformers for the other diffraction orders.