Magnetocaloric GdMn_1-xRu_xSi compounds with x = 0 - 1 for gas liquefaction

Ternary intermetallic compounds based on rare-earth metals are characterized by high values of the magnetocaloric effect (MCE) and magnetoresistance, making them suitable materials for a variety of innovative, environmentally friendly and efficient applications. Magnetic refrigeration, for example, is a potential candidate for environmentally friendly gas liquefaction and for preventing gas from evaporating during storage. As an example, liquid nitrogen is often used as a final refrigerant for liquefied natural gas at 111 K. Novel intermetallics GdMn_1−xRu_xSi with a tetragonal CeFeSi-type structure (P4/nmm), were synthesized, with x = 0, 0.2, 0.5, 0.8 and 1 [1]. Their Curie temperature T_C changes from 78.3 to 320 K with a change in manganese content. The electronic structure and magnetic moments of GdMn_1-xRu_xSi intermetallic compounds were calculated using the theoretical DFT+U method. The calculated total magnetic moments of GdMn_1-xRu_xSi also show reduced values for intermediate Ru concentrations. In the GdMn_1-xRu_xSi system, MCE occurs during a second-order phase transition and in a wide temperature range from 78.3 (which is near the boiling point of liquid nitrogen at 77.4 K) to 320 K. The GdMn_1-xRu_xSi system, with x = 0 - 1, is of practical interest for the liquefaction of gases, including nitrogen. A cassette can be made from compounds within this range with slightly varying chemical compositions. Due to their properties, the intermetallic GdMn_1-xRu_xSi compounds are novel, more efficient magnetocaloric materials suitable for the liquefaction of nitrogen and other gases.

1. Platonov, S.P.; Kuchin, A.G.; Volegov, A.S.; Gaviko, V.S.; Mukhachev, R.D.; Lukoyanov, A.V.; Yakovleva, M.Yu. The GdMn_1-xRu_xSi Compounds Cassette for Magnetocaloric Nitrogen Liquefaction. Physica B: Condensed Matter 2024, 685, 416060. https://doi.org/10.1016/j.physb.2024.416060