Crystal structure of the oxides BaCu${\mathrm{Gd}}_2$${\mathrm{O}}_5$ and ${\mathrm{Ba}}_2{\mathrm{Cu}}_3\mathrm{Gd}{\mathrm{O}}_{7-x}$

We have grown crystals of BaCu${\mathrm{Gd}}_2$ ${\mathrm{O}}_5$ and ${\mathrm{Ba}}_2{\mathrm{Cu}}_3\mathrm{Gd}{\mathrm{O}}_{7-x}$ and determined their structures by single-crystal x-ray diffraction. Green and black BaCu${\mathrm{Gd}}_2$ ${\mathrm{O}}_5$ are roughly identical. In the refinement of ${\mathrm{Ba}}_2{\mathrm{Cu}}_3\mathrm{Gd}{\mathrm{O}}_{7-x}$ a value of $x=0.5\mathrm{}$ is obtained. The existence of oxygen vacancies is compatible with an incommensurable system and also with high-order superstructures.