Effect of carbonate incorporation on the structural and superconducting properties of the double chain compound Y₂Ba₄Cu₇O_15−x

Structural investigations on powder samples of Y2Ba4Cu7O15–x with different carbonate content have been performed. Powder x‐ray Rietveld refinements showed the remarkable influence of carbonate incorporation on the lattice parameters. Most important is the decrease of Tc with increasing carbonate content. We assign these effects to an incorporation of the carbonate ion into the crystal lattice, copper vacancies at the Cu(1) position and a possible misorientation of the copper oxygen single chains. No change of the structure (e. g. superstructure) could be found. Copyright © 1994 Verlag GmbH & Co. KGaA, Weinheim