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Monday, 26 October 2015

Prof José Ramón Galan-Mascaros offers a Seminar about spin crossover

During his presentation, Prof. José Ramón Galan-Mascaros explored the state of the art in the field, as exemplified by the versatility observed in the family of triazole-based spin crossover compounds. The speaker was introduced by CSIC Research Prof Daniel Ruiz, Group Leader at ICN2.

ICREA Research Prof. José Ramón Galan-Mascaros, from theInstitute of Chemical Research of Catalonia (ICIQ), offered on October 22 an ICN2 entitled “Adventures in spin crossover phenomena”. The talk was introduced by CSIC Research Prof Daniel Ruiz, Group Leader at ICN2.

Spin crossover compounds are a paradigmatic example of bistable materials. In such metal complexes the magnetic state can be tuned from a low-spin (LS) configuration into a low-lying metastable high-spin configuration through external stimuli. They have been postulated as bulk components for new generation memory devices and sensors.

The most remarkable examples have been obtained in the coordination chemistry of octahedral FeII, since the electronic change from diamagnetic S = 0 to the paramagnetic S = 2 metastable state induces major changes in magnetic and spectroscopic properties and even in size. When coordinated by triazole (trz) ligands, trz-bridged FeII 1D chains are formed with spin transition occurring over room temperature, and exhibiting wide thermal hysteresis cycles (> 40 K), with those features easily tuned by functionalization of the trz or by substitution of the counter ions.

During his presentation, Prof. José Ramón Galan-Mascaros explored the state of the art in the field, as exemplified by the versatility observed in the family of triazole-based spin crossover compounds, where chemical design may yield (giant) memory effect in the solid state, in nanostructures, in solution and in hybrid conducting materials.