Variable Temperature and Pressure XRD on Barocaloric Organic Ionic Plastic Crystals

In this proposal we aim to perform variable-temperature (VT) and variable-pressure (VP) synchrotron powder x-ray diffraction experiments on organic ionic plastic crystals ([Ci3mpyr][TFSI], [Ci3mpyr][FSI], [N2222][TFSI], and [C2mmor][FSI]), recently reported as breakthrough barocaloric materials for eco-friendly and efficient heating and cooling technologies (J. Pringle et al. Science, 2025, 387, 56). These particular barocaloric materials are one of the scarce materials that present pressure-induced solid-solid phase transitions with colossal thermal changes (ΔS > 200 J K-1 kg-1) under the application of significantly low pressures (Δp < 600 bar) and that can operate in a temperature range of interest for conventional refrigeration technologies (230-300 K). The obtained results will shed light towards enhanced design and thermal properties optimization of future barocaloric organic inorganic plastic crystals.