A relation between the binding energy of atoms in crystals and the speed of sound has been derived on the basis of the Mie and Lennard-Jones potentials. Comparing with other results taken from literature, its application to the 12-6 Lennard-Jones potential shows a quite good agreement in the case of rare gases. As far as metals are concerned, the deviations are higher but consistent with the accuracy of the method used to compute them . Results for rare earth metals show higher discrepancies. Consistence is also observed in the case of the Mie potential, even though a difference of about 40% is observed for platinum. It is emphasized that this relation, expressed by Eq. ( ), has only a theoretical purpose. It adopts some approximations such as to limit atoms interactions to nearest neighbors, therefore it is not supposed to be used for detailed calculations of interatomic interactions in crystals, where appropriate and accurate force fields have been derived. Moreover, these force fields are applicable to all kinds of crystals and to other forms of condensed matter, whereas our approach is limited to crystals of pure elements.