123 Phases formed in the YLnKCu3Ox (Ln = La, Nd) systems

A 123 tetragonal phase with the doubled unit cell volume (the "336" phase), the unit cell parameters a = b = 0.5544(5) nm, c = 1.1958(8) nm, and a composition close to Y 2 Nd 2 . 2 4 K 1 . 7 6 Cu 6 O 1 4 . 1 [Z(Q) = 7.24], in which K occupies Ba positions, is prepared using routine nitrate technology. The synthesis of a similar phase containing lanthanum and potassium under the specified conditions failed.