Complex Oxide Dy_2Mn_(2/3)Re_(4/3)O_7 with a Pyrochlore Structure

摘要

The new complex Dy_2Mn_(2/3)Re(4/3)O_7 has been prepared by solid-phase synthesis from Dy_3ReO_8, ReO_2, metallic Re, and Mn_2O_3. The new oxide crystallizes in the hexagonal system with the unit-cell parameters a = 14.725(5) A, and V = 3271 A~3. The magnetic susceptibility, measured in a temperature range of 2-400 K, follows the Curie-Weiss law in a range of 100-400 K and provides evidence for the presence of the Mn~(2+)-Re~(5+) valence combination. Measurements of the magnetization depending on the applied magnetic field strength demonstrate that the new oxide possesses a spontaneous magnetic moment at 2 K.