The GdMn1-xRuxSi compounds cassette for magnetocaloric nitrogen liquefaction

Abstract

New intermetallic compounds GdMn1-xRuxSi, x = 0–1 with a tetragonal structure of the CeFeSi-type (P4/nmm) have been synthesized. For GdMn1-xRuxSi, Curie temperature TC drops sharply from 320 K (x = 0) to 78.3 K (x = 1), while the magnetocaloric effect varies from 1.84 J/kgK (x = 0) to 4.94 J/kgK (x = 1) with a change in the magnetic field of 0–17 kOe. Thus, the GdMn1-xRuxSi magnetic refrigeration compounds operate at temperatures from 320 K to 78.3 K, close to the nitrogen liquefaction temperature of 77.4 K. Therefore, the GdMn1-xRuxSi system, where x ranges from 0 to 1, could be of practical interest for nitrogen liquefaction, provided that these alloys are assembled into a cassette with a single large refrigerant capacity. The electronic structure and magnetic moments of the GdMn1-xRuxSi intermetallic compounds were calculated using the DFT + U theoretical method.