Theoretical investigation of crystalline electric field influence on the magnetocaloric effect in the cubic praseodymium system PrNi2

Abstract

We report a theoretical investigation of the magnetocaloric effect in paramagnetic intermetallic $\mathrm{Pr}{\mathrm{Ni}}_{2}$. We choose this particular compound because it presents high cubic symmetry, and two sets of crystalline electrical field parameters were reported, allowing a systematic study. In one of these sets, the magnetic entropy increases upon applied magnetic field in the low temperature region $(T<10\phantom{\rule{0.16em}{0ex}}\mathrm{K})$ for $H=5\phantom{\rule{0.16em}{0ex}}\mathrm{T}$. This anomaly was investigated through a model Hamiltonian which includes the magnetic, exchange, and crystalline electric field interactions. The simulated curves of the temperature dependence of isothermal entropy variation and adiabatic temperature change present the inverse magnetocaloric effect, which is not expected for a paramagnetic system.