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Updated: May 6, 2026

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
High-temperature photo-induced switching and pressure-induced transition in a cooperative molecular spin-crossover
Gavin A Craig1, Jose Sánchez Costa, Olivier Roubeau
1Departament de Química Inorgànica, Universitat de Barcelona, Diagonal 645, 08028 Barcelona, Spain. guillem.aromi@qi.ub.es.
Abstract:
The thermal and photo-induced switching properties of the recently published molecular spin crossover complex [Fe(H4L)2](ClO4)2·H2O·2(CH3)2CO () have been investigated in detail through Raman spectroscopy. Magnetometric and single crystal X-ray diffraction kinetic studies within the hysteresis loop have proven its metastable character, which allowed establishing the shape of the true, quasi-static hysteresis loop. This is related to the proximity of the temperatures of the thermal high to low spin SCO (T1/2↓) to those of the relaxation of the thermally or photo-generated metastable states (T(TIESST) and T(LIESST), respectively). Green light irradiation within the hysteresis loop results in a complete low to high spin photo-switch. In addition, the SCO of at room temperature can be induced by applying pressure, as followed by Raman spectroscopy.
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