Giant barocaloric effects were recently reported for spin-crossover materials. The volume change in these materials suggests that the transition can be influenced by uniaxial stress, and give rise to giant elastocaloric properties. However, no measurements of the elastocaloric properties in these compounds have been reported so far. Here, we demonstrated the existence of elastocaloric effects associated with the spin-crossover transition. We dissolved particles of ([Fe(L)₂](BF₄)₂, [L=2,6di(pyrazol-1-yl)pyridine]) into a polymeric matrix. We showed that the application of tensile uniaxial stress to a composite film resulted in a significant elastocaloric effect. The elastocaloric effect in this compound required lower applied stress than for other prototype elastocaloric materials. Additionally, this phenomenon occurred for low values of strain, leading to coefficient of performance of the material being one order of magnitude larger than that of other elastocaloric materials. We believe that spin-crossover materials are a good alternative to be implemented in eco-friendly refrigerators based on elastocaloric effects.

We have investigated the magnetic and magnetocaloric properties together with transition hysteresis of Ni48.5Ti1.5Mn36In14 magnetic shape memory alloy under several magnetic field levels at a temperature interval from 400 K down to 10 K. We observe a small magnetization difference between austenite and martensite phase with a thermal hysteresis around the martensitic transition. We have investigated the minimum magnetic field required to start and to complete the magnetostructural phase transition. We observed small values of inverse and conventional magnetocaloric effect around martensitic transition and around Curie temperature of austenite, respectively. This attributed to the hysteresis loss during the martensitic transformation.