The phase formation and electrical and magnetic properties of R-E-subs
tituted compounds La1.6Sr0.4Ca1-xRExCu2O6 (R-E = rare-earth elements)
were investigated systematically. It was found that all the rare-earth
elements (La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Y, Ho, Er, Tm, Yb) except C
e form 212-type compounds. Their structures were verified by Rietveld
structure refinement. (C) 1998 Elsevier Science Ltd.