Six copper (II) compounds with an anion of glutaric acid (H$_2$L) were synthesized from aqueous solution. Furthermore, an additional nitrogen compound was added during the synthesis (2-nicotinamide, 3- isonicotinamide, 4- 3-hydroxypyridine, 5- 2-aminopyridine, 6- guanidinium carbonate), which is bound in the final compounds. This was noticed from the IR spectra. None of the compounds in this system was found in the CSD crystallographic database for the known crystal structures. On the other hand, a compound 1 with the formula CuL(H$_2$O) was described in the literature. Its identity was confirmed with the powder XRD data. Some similarities were found also for a compound 2in another source. Despite XRD and IR significant match, the final identity was not confirmed, as the nitrate ions are mentioned in that formulae, however it was not taken during my synthesis procedure for 2. All compounds 1-6 are colored blue or green and differ from each other in the color and shape of the product. Smaller differences are visible in the UV-Vis spectra. Nevertheless, the absorbed light 550-700 nm in the spectra coroborrates with the complementary colour of the compounds. All compound’s IR spectra reveal bands of the asymmetric and symmetric stretching vibrations of the carboxylate groups at 1570 and 1400 cm$^{-1}$. These confirm a presence of the glutaric acid anion (L). The characteristic band for C=O bond (2, 3) at 1680 cm$^{-1}$ can be seen in the IR spectra. Bands of NH2 groups are found above 3000 cm$^{-1}$ (2, 3, 5, 6).
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