Spectrometric measurements and DFT studies on new complex of copper (II) with 2-((E)-9-ethyl-3-(2-(6-(4-methylpyridin-2-yl)pyridin-3-yl)vinyl)-9H-carbazole

•The FT-IR and UV-Vis of the title compound have been recorded experimentally.•Optimized geometry, vibrational frequencies and intensities of the title compound are obtained with DFT methods.•The complete assignments of the experimental spectra are performed on the basis of the potential energy distribution (PED).•The absorption spectra of the compound were computed both in gas-phase and in CH3OH solution.

The molecular structure of a new complex of copper (II) with (E)-9-ethyl-3-(2-(6-(4-methylpyridin-2-yl)pyridin-3-yl)vinyl)-9H-carbazole ([Cu2(emppc)2Cl2]Cl2) was optimized with B3LYP/LanL2DZ, PBE1PBE/LanL2DZ and M062X/LanL2DZ theoretical level. The ligand, (E)-9-ethyl-3-(2-(6-(4-methylpyridin-2-yl)pyridin-3-yl)vinyl)-9H-carbazole (emppc), binds to Cu(II) ions with a bi-dentate mode, two Cl− serve as bridging ligand, each Cu(II) ion has a highly distorted tetrahedron coordination geometry. With M062X/LanL2DZ theoretical level, the calculated interaction energies of Cu(II) with coordination atoms N are between 183.3–200.0 kJ mol− 1 for α spin and 319.4–324.9 kJ mol− 1 for β spin, and interaction energies of Cu(II) with coordination atoms Cl atom are 248.0–252.4 kJ mol− 1 for α spin and 332.6–333.6 kJ mol− 1 for β spin. The experimental Fourier transform infrared spectrum was assigned. The calculated IR based on B3LYP/LanL2DZ, PBE1PBE/LanL2DZ and M062X/LanL2DZ methods were performed and compared with experimental results. The UV–Vis experimental spectra of [Cu2(emppc)2Cl2]Cl2 was measured in methanol solution. The calculated electronic spectrum was performed with TD/M062X and PCM-TD/M062X methods with LanL2DZ basis set. The nature bond orbital analysis and temperature dependence of the thermodynamic properties were calculated with the same methods.

Graphical abstractExperimental and DFT study of the structural and spectroscopic properties of [Cu2(emppc)2Cl2]Cl2 has been reported.Figure optionsDownload full-size imageDownload as PowerPoint slide