Crystal Structures and Electrical Properties of L1.5Ba1.5Cu3Oy(L=La, Pr, Nd, Sm, Eu, Gd, Y and Yb)

Abstract
The L1.5Ba1.5Cu3O y compounds for L=lanthanides have been investigated by X-ray powder diffraction analysis and electrical resistivity measurement. A single L1.5Ba1.5Cu3O y phase has been firstly obtained in the samples for L=Nd, Sm and Eu as well as La and Pr exhibiting the semiconductor-like behavior of resistivity down to about 10 K. This single phase has not been obtained in the samples for L=Gd, Y and Yb having the LBa2Cu3O y and L2BaCuO y phases and exhibiting the superconductivity. The stability of the L1.5Ba1.5Cu3O y single phase is found to depend on the L3+ ion radius and sintering condition.