Luminescent Detection of Photomagnetic Effect in a Near‐Infrared Emissive Neodymium(III)–Octacyanidotungstate(IV) Framework

Abstract Photomagnetic materials form a class of magnetic systems, in which light irradiation changes their magnetization. Photomagnetic behavior is often observed in spin transition materials, including spin‐crossover complexes, and can lead to long‐range magnetic ordering. Photo‐induced magnetization can affect different physical properties, including second harmonic generation. Still, despite a growing number of luminescent spin‐crossover systems, the simultaneous switching of both magnetism and luminescence was not yet explored. In this regard, we present systematic studies for a novel coordination polymer composed of anionic Nd III –[W IV (CN) 8 ] 4– layers, crystallizing with chiral organic cations embedded in the interlayer space. Not only we observe and rationalize theoretically near‐infrared emission of Nd III centers sensitized by [W IV (CN) 8 ] 4– units, but we also found a plausible pathway to track the photomagnetic effect throughout the analysis of the Nd 3+ excitation spectra and their temperature dependence. The observed thermally reversible effects in luminescence were correlated with the results of photomagnetic studies, providing an attractive pathway to monitor the light‐induced magnetization changes through a photoluminescent read‐out.