NMR study of 59Co nuclei in EuBaCo2O5+x (x=0 and 0.5)

Abstract NMR measurements of 59 Co nuclei in EuBaCo 2 O 5+ x ( x =0.52 and 0.02) are carried out to clarify the spin state of Co ions. We observe in the antiferromagnetic state of the x =0.52 sample three groups of NMR lines with high, intermediate and low hyperfine fields. These results do not agree with the crystal structure at room temperature.