Magnetic Phase Transition and Magnetocaloric Effect in Ternary Er2Ni2Ga Compound.

The crystal structure, magnetism, and magnetocaloric effect (MCE) were investigated in ternary Er2Ni2Ga compound. The Er2Ni2Ga belongs to W2B2Co-type structure (orthorhombic, space group Immm). The magnetization measurements indicate that Er2Ni2Ga suffers a field-induced metamagnetic transition (antiferromagnetic–ferromagnetic) below Néel temperature (TN) of 7.1 K. Inverse MCE occurs with magnetic field change ($\Delta H$) lower than 0–30 kOe and at low temperatures, whereas normal reversible MCE happens with higher $\Delta \text{H}$. The calculated $-\Delta S_{M}$ (magnetic entropy change) has a peak value of 12.93 J/kg K (~9 K) with refrigerant capacity value of 265 J/kg (5–30 K) for Er2Ni2Ga under $\Delta H$ of 0–70 kOe. [ABSTRACT FROM AUTHOR]