Abstract
An anomalous high antiferromagnetic Néel temperature T N (Pr) of 8 K are reported for the argon-treated Bi-2212 compound Bi 2 Sr 2 PrCu 2 O 8+δ . In this compound, a high Cu ordering temperature T N (Cu) of 350 K was also observed. For the isostructural Gd compound Bi 2 Sr 2 GdCu 2 O 8+δ , a Curie-Weiss paramagnetic intercept θ p of -2.5 K is consistent with antiferromagnetic T N (Gd) of 1.8 K reported before. For non-magnetic Y compound Bi 2 Sr 2 YCu 2 O 8+δ , only Cu ordering around 350 K was observed.