Bibliogr.

Two novel copper(II) l–argininato coordination compounds: trans–]· (1) and [Cu(l–Arg)(phen)Br]Br· (2) (where l–Arg = l–arginine and phen = 1,10–phenanthroline) were synthetized and comprehensively investigated to clarify the impact of the bromide, acting as two counterions in 1 and as both a caunterion and a ligand in 2, on the self–organization and molecular and electronic structures. Data on the crystal, molecular and electronic structures of compounds 1 and 2 were obtained via X–ray diffraction. These results formed the basis for the subsequent theoretical characterization of intramolecular interactions via electron density distribution in metal–ligand bonds using the atoms in molecules (AIM) method, and characterization of intermolecular interactions via Hirshfeld surface analysis (HAS). Additionally, the charge on copper(II) ions modified by electron transfer from ligands was determined using the natural bond orbitals (NBO). Furthermore, the following spectroscopic techniques were applied to establish correlations between molecular and electronic structures: FT–IR, Raman, NIR–VIS–UV, X– and Q–band EPR, and fluorescence.