Structural study of pressure-induced magnetic phase transitions in manganites Pr_0.7Ca_0.3Mn_1-yFe_yO₃ (y?=?0, 0.1)

A crystal and magnetic structure of manganites Pr_0.7Ca_0.3Mn_1−y Fe _y O₃ (y = 0, 0.1) has been studied by means of powder neutron diffraction at pressures up to 4 GPa in the temperature range 15-300 K. Under high pressure, an appearance of A-type antiferromagnetic state in both systems was observed. Both compounds exhibit anisotropic compression of the lattice which leads to the apical compression of MnO₆ octahedra along the crystallographic b-axis. The calculated from obtained structural data pressure dependence of the charge-carrier bandwidth is in a qualitative agreement with observed pressure behavior of insulator-metal transition temperature within the framework of the double-exchange model.

Keywords:

• Pressure
• Crystal And Magnetic Structure
• Manganites