Exploring the Vibrational Side of Spin‐Phonon Coupling in Single‐Molecule Magnets via (161)Dy Nuclear Resonance Vibrational Spectroscopy

Synchrotron‐based nuclear resonance vibrational spectroscopy (NRVS) using the Mössbauer isotope (161)Dy has been employed for the first time to study the vibrational properties of a single‐molecule magnet (SMM) incorporating Dy(III), namely [Dy(Cy(3)PO)(2)(H(2)O)(5)]Br(3)⋅2 (Cy(3)PO)⋅2 H(2)O ⋅2 EtOH. The experimental partial phonon density of states (pDOS), which includes all vibrational modes involving a displacement of the Dy(III) ion, was reproduced by means of simulations using density functional theory (DFT), enabling the assignment of all intramolecular vibrational modes. This study proves that (161)Dy NRVS is a powerful experimental tool with significant potential to help to clarify the role of phonons in SMMs.