Experimental, Theoretical, Characterization and TD-DFT Analysis of a Complex [Cu(CAP) 2 Cl 2 ]

The present paper work investigates a new complex bis (4-amino-2-chloropyridinium) dichlorocuprate(II) with the formula [Cu(C 5 H 5 ClN 2 ) 2 Cl 2 ] abbreviated as [Cu(CAP) 2 Cl 2 ]. The sample was characterized by X-ray diffraction, Hirshfeld surface analysis, thermal analysis, FT-IR, FT-Raman and CP/MAS-NMR spectroscopy and optical properties. It was crystallized in the monoclinic system with space group P2 1 /n. The crystal structure was stabilized by the presence of N–H⋯Cl hydrogen bond, forming a three-dimensional network. The Hirshfeld surfaces and the 2D fingerprint plots were analysed in the intermolecular interactions within the crystal network. Solid state CP/MAS-NMR spectra showed five isotropic resonances, 13 C confirming the existence of five non-equivalent carbon atoms of the asymmetric unit determined by X-ray diffraction. The density functional theory using B3LYP/LanL2DZ basis sets, showed an excellent overall agreement between the calculated values and the experimental data. The energy gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital was determined by a time-dependent DFT approach.