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

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 NdIII-[WIV(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 NdIII centers sensitized by [WIV(CN)8]4- units, but we also found a plausible pathway to track the photomagnetic effect throughout the analysis of the Nd3+ 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.