Theoretical investigation of entropic barocaloric effect in spin-crossover systems

• Published in: Journal of magnetism and magnetic materials Vol. 564; p. 170121
• Main Authors: von Ranke, P.J., Alho, B.P., Ribas, R.M., Nobrega, E.P., de Sousa, V.S.R., Ribeiro, P.O.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.12.2022
• Subjects: Barocaloric effect; Solid state refrigeration; Spin-crossover; Solid state refrigeration; Spin-crossover; Barocaloric effect
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2022.170121

•Barocaloric effect in spin-crossover materials (SCO).•Magnetic, vibrational and configurational entropies contributions at low–high spin phase transition.•Conditions for the appearance of hysteresis in (SCO)-compounds.•Obtention of molecular volume changing, in (SCO)-materials, through the barocaloric effect. We report a theoretical investigation of the entropic barocaloric effect in a spin crossover system. From our model Hamiltonian, the total entropy, which includes the contributions from the lattice (vibrational), magnetic and configurational entropies, was obtained and worked out for a systematic study of the barocaloric effect. The barocaloric effect was parametrically investigated in three scenarios: second order, threshold of second-first order and first order phase transition. Besides, a procedure for obtaining the molecular volume change during the low spin to high spin phase transition conversion was proposed, through the entropic barocaloric measurements.