Анотація:
In the work the temperature dependence of magnetization, entropy changes, and the Curie temperature of La₀̣.₇Ba₀.₃MnO₃ using Monte Carlo method and Heisenberg model were investigated. We used the magnetic exchange parameters from the first-principles calculations. In the simulation, magnetic Mn³ᐩ and Mn⁴ᐩ ions are described by classical Heisenberg spins, while oxygen, lanthanum and calcium ions are considered as non-magnetic. Mn magnetic ions are distributed on R3c lattice according to the perovskite structure of the manganite. The Curie temperature and magnetocaloric effect values obtained during the theoretical simulations are in a good agreement with the experimental data.