Synthesis of new praseodymium-based cuprates (Pr,Cd)Sr2YCu2Oy and (Pr,M)Sr2(Gd,Ce)2Cu2Oz (M = Cn,Zn)

Two new families of praseodymium-based cuprates, (Pr,Cd)Sr ₂YCu ₂O _y and (Pr,M)Sr ₂(Gd,Ce) ₂Cu ₂O _z (M dbnd Cu,Zn), have been synthesized and identified by XRD, ED analyses. (Pr,Cd)-1212 crystallizes in a orthorhombic cell with a=3.838Å, b=3.812Å, c=11.82Å, (Pr,M)-1222 is of a tetragonal cell with a=3.837Å, c=28.977Å for (Pr _0.5Cu _0.5)Sr ₂(Gd _1.2Ce _0.8)Cu ₂O _z and a=3.824Å,c=28.990Å for (Pr _0.5Zn _0.5)Sr ₂(Gd _1.2Ce _0.8)Cu ₂O _z. Their ED patterns show that no superstructure exists in the two series of Pr-based cuprates. These compounds are semiconductirs under the present experimental conditions.