= Mn, Ni, Fe) complexes

Layered magnetic chalcogenides have become increasingly important over the last decade because they offer a unique platform for combining the complexity of bulk materials with the tunability of few- and single layer systems. These van der Waals complexes have been well studied by Raman spectroscopy, however, infrared spectroscopy is vastly underexplored due to the inability to overcome the diffraction limit. It is these ungerade infrared active modes that are vital in understanding material functionality. Synchrotron infrared nanospectroscopy, a fusion of near-field optical microscopy with high brightness infrared synchrotron radiation, has overcome this fight for photons and enabled a better understanding of size-induced effects, including symmetry breaking, that are quite different from the single crystal. This approach will be illustrated with members of the MPS₃ (M= Mn, Ni, Fe) family of complex chalcogenides.