Resistivity and critical temperature of (La_1-xPr_x)_0.7Ca_0.3MnO₃

An empirical formula of the critical temperature that is concentration dependent for polycrystalline (La_1-xPr_x)_0.7Ca_0.3MnO₃ is presented in this paper. With this formula, the temperature dependence of resistance is simulated for various values of x by using the random resistor network model and the Monte Carlo method. The hysteresis effect in \rho -- T curves is reasonably explained. The simulation results are in good agreement with the relevant experimental measurements.