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Updated: Jan 21, 2026

Nanostructured Ag-zeolite Composites as Luminescence-based Humidity Sensors
Published on: November 15, 2016
Interplay between spin-crossover and luminescence in a multifunctional single crystal iron(ii) complex: towards a new
Bouabdellah Benaicha1, Khanh Van Do2, Aymen Yangui3
1Univ. Brest , CNRS , CEMCA , 6 Avenue Victor Le Gorgeu, C. S. 93837 , 29238 Brest Cedex 3 , France .
Abstract:
We present a new example of a mononuclear iron(ii) complex exhibiting a correlated spin-crossover (SCO) transition and strong fluorescence, whose coordination sphere is saturated, for the first time, by six phosphorescent ligands. The interplay between SCO and light emission properties in the thermal region of the spin transition was investigated by means of magnetic, fluorescence, optical absorption and optical microscopy measurements on a single crystal. Overall, the results show an excellent correlation between fluorescence and magnetic data of the present gradual transition, indicating an extreme sensitivity of the optical activity of the ligand to the spin state of the active iron(ii) ions. These results open the way for conceiving new prototypes of pressure and temperature sensors based on this synergy between SCO and luminescence properties. In particular, the fact that cooperative SCO material is not a prerequisite for obtaining such synergetic effects, is useful for the design of thin films or nanoparticles, in which the cooperativity is reduced, for appropriate implementation in nanosized devices to enhance the sensing properties at the nanoscale.
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