Influence of a-site rare earth cation substitution on the structural and magnetic properties of nano-crystalline Ln2CoMnO6 (Ln = Pr, Sm, Gd, Ho, Yb)

A-site rare earth cation substitution in double perovskite (DPOs) Ln2CoMnO6 (Ln=Pr, Sm, Gd, Ho, and Yb) and its effect on their structural and magnetic properties is investigated in this paper. A comprehensive investigation of the structural and magnetic properties is conducted, and a rare earth ionic radii dependent comparative analysis is presented. In our observations, we noted a reduction in lattice parameters by approximately 6% along with a decrease in the magnetic phase transition as the ionic radii of A-site cation decreased from Pr to Yb. Specifically, we observed a decline in TC from 172 K for the largest Pr cation (1.13 Å) to 48 K for the smallest Yb cation (0.99 Å) in our study. These findings demonstrate the significant influence of rare earth cation substitution on the physical properties of the DOPs.