Research Highlights

Pressure-enforced multifunctionality in a spin-crossover photomagnet

Photomagnetic compounds are usually created by assembling pre-organized individual molecules into rationally designed molecular architectures via the bottom-up approach. The CSEC group of Prof. Konstantin Kamenev in collaboration with colleagues from Jagiellonian University (Kraków, Poland) for the first time demonstrated that a magnetic response to light can also be enforced in a non-photomagnetic compound by applying pressure. Magnetic, structural and optic properties of the non-photomagnetic cyano-bridged FeII-NbIV coordination polymer {[FeII(pyrazole)4]2[NbIV(CN)8].4H2O}n (FeNb) were studied under a range of varying thermodynamic paramenters such as magnetic field, high pressure and low temperature in combination with illumination by light. The study revealed a wide spectrum of pressure-related functionalities including the light-induced magnetization and piezochromism. The study for the first time demonstrated that a complex magnetic behaviour as well as a variety of intriguing properties can be induced by adjusting the thermodynamic conditions. This approach to multifunctionality by manipulating temperature, pressure, and light is the first example of such a level of solid matter control that forces the photomagnetic switching. This  is a new concept that can be adapted to other potentially photoactive molecular solids, opening a new field of high-pressure photomagnetic materials as such systems allow manipulation and comparison of various energy scales which is of utter importance for theoretical modelling.