Large magnetocaloric effect in Gd(Mn,Cr)Si at room temperature

Novel ternary compounds with rare earth metal GdMn 1- x Cr x Si, x = 0–0.6, featuring a tetragonal structure of the CeFeSi ( P 4/ nmm )-type have been studied. These compounds were synthesized, and their magnetic properties and magnetocaloric effect (MCE) were evaluated. It was found that the MCE for compositions x = 0.4, 0.5 is approximately twice as large as for x = 0 or 0.1. Apparently, the maximum MCE for the compositions x = 0.2–0.6 is due to the summation of changes in magnetic entropy during magnetic ordering of the Gd and 3 d subsystems at close or coinciding temperatures. Our theoretical DFT+U calculations confirm different magnetic orderings in the Gd and 3 d sublattices in GdMn 1-x Cr x Si. The GdMn 0.6 Cr 0.4 Si compound shows promise for use in household magnetic refrigerators due to its notable magnetocaloric effect of 3.16 J/kgK at T C = 310 K and a refrigerant capacity of 106.8 J/kg with a field change from 0 to 17 kOe. • New compounds GdMn 1- x Cr x Si, x = 0–0.6 of the CeFeSi ( P 4/ nmm )-type have been synthesized. • For x = 0, 0.1 two magnetic orderings at different T are observed for Gd, 3 d subsystems. • For x = 0.2–0.6 magnetic orderings Gd and 3 d subsystems occur at close or coinciding T . • Maximum MCE( T ) for x = 0.2–0.6 is only one and larger as for x = 0, 0.1 with two maximum. • For x = 0.2–0.6 summation is of changes in entropy during ordering Gd and 3 d subsystems.