Abstract
In this work, the magnetization isotherms, the magnetic entropy change and the specific heat change in MnFeP0.45As0.55 and MnFeP0.47As0.53 transition metal-pnictides were modeled by the mean-field and the Bean-Rodbell models. The first-order magnetic phase transition (FOMPT) of these compounds was confirmed by examinating of the Bean-Rodbell parameter, eta. Our consideration of the Bean-Rodbell model, which is a complement of the mean-field theory, in the emergence of the magneto-volume effects, led to a good agreement between the simulated and the experimental results. (C) 2021 Published by Elsevier B.V.