Influence of ionic substitution on the magnetic behaviour of Y2Cu2O5
Abstract
The influence of the substitution of Cu or O by various elements on the magnetic properties of Y2Cu2O5 has been studied. The substitution of Cu by metal ions with unpaired d electrons (M = Co2+, Ni2+) makes the superexchange in Cu2O8 chains stronger, but the substitution by those metal ions without unpaired electrons (M = Zn2+, Mg2+) makes the superexchange weaker. The substitution of O by S also makes the superexchange weaker. Magnetic properties of Y2Cu2 –xMxO5 and Y2Cu2O5 –ySy were studied between 77 K and room temperature. Samples were characterized by X-ray diffraction (XRD), electron paramagnetic resonance (EPR) and thermal gravimetry (TG).