Crystalline and magnetic properties of Er and Yb chromites modified by Mn and Ca cations

Magnetic measurements indicate an increase of the ferromagnetic behavior when Ca2+ is incorporated into the lattice, with an expected transformation of Mn3+ into Mn4+, and its associated ferromagnetic exchange interactions. Competition between ferromagnetic Mn3+-Mn4+, Mn3+-Cr3+ and antiferromagnetic Cr3+-Mn4+, Yb-TM interactions (TM: transition metal) leads to complex magnetic ordering in the ytterbium chromites, although double exchange Mn3+-Mn4+ interactions predominate and suppress the spin reversal expected for the pure YbCrO3 material.