The magnetic properties of disordered Nd0.5Ba0.5Mn0.5Fe0.5O3−δ/2 and
ordered NdBaMnFeO6−δ perovskites were investigated
through temperature- and field-dependent DC-magnetization measurements.
The temperature dependence of magnetic susceptibilities revealed that
antiferromagnetic ordering occurs at temperatures below 185 K for
the disordered Nd0.5Ba0.5Mn0.5Fe0.5O3‑δ/2 sample, whereas the ordered
NdBaMnFeO6−δ perovskite exhibited a paramagnetic
state throughout the entire temperature range examined. Notably, the
disordered sample exhibited a glassy state, even at room temperature,
which transformed into an antiferromagnetic state under higher applied
magnetic fields. The magnetic ordering in the disordered Nd0.5Ba0.5Mn0.5Fe0.5O3‑δ/2 perovskite and the magnetic-disordering state in the structurally
ordered NdBaMnFeO6‑δ perovskite could be attributed
to the alteration of the oxidation state of Mn.