Unraveling the impact of nonmagnetic Sc substitution on the magnetic properties of La2NiMnO6 double perovskite

The structural, electronic, and magnetic properties of a sol-gel prepared series of La2Ni1-xScxMnO6 compounds have been extensively studied using x-ray diffraction, x-ray absorption near edge structure, and dc magnetization techniques, respectively. The entire series was isostructural and exhibited the La2NiMnO6 double perovskite P2(1)/n monoclinic structure. The nonmagnetic Sc3+ substitution led to the evolution of competing magnetic phases in La2Ni1-xScxMnO6. The substitution also caused an increase in lattice parameters, cell volume, and bond lengths. Consequently, Sc3+ dilution resulted in a dramatic decrease in Curie temperature, suggesting a reduction in the strength of the Ni2+-O2--Mn4+ superexchange ferromagnetic interaction. The Sc3+ substitution generated antisite defects, which significantly suppressed the saturation magnetization of the system. The competing magnetic interactions observed in the La2Ni1-xScxMnO6 system are discussed in terms of cation disorder, cation valances, and changes in the bond lengths/angles, caused by the Sc3+ substitution.

Automated summary

The structural, electronic, and magnetic properties of La2Ni1-xScxMnO6 compounds were extensively studied, revealing that Sc3+ substitution led to the evolution of competing magnetic phases and caused changes in lattice parameters.