Synthesis, characterization and DFT studies of two new silver(I) complexes with 3,4-lutidine

• The [Ag(34lut)3(OAC)]; 1 and [Ag(34lut)2(TFA)]; 2 were synthesized and identified.
• Both complexes having distorted tetrahedral coordination geometry around silver ion.
• The OAC is monodentate in 1 while the TFA is bidentate in 2.
• NBO analyses confirmed the coordination behavior of the COO group in 1 and 2.
• 1 is predicted to have higher NLO properties than 2.

The synthesis, characterization and molecular structure of two new Ag(I) complexes with 3,4-lutidine (34lut) have been reported. The [Ag(34lut)3(OAC)]; 1 and [Ag(34lut)2(TFA)]; 2 complexes, where OAC and TFA are acetate and trifluoroacetate respectively, have been characterized using elemental analysis, FTIR, NMR and mass spectra. Their molecular structures were calculated using DFT quantum chemical calculations. Both 1 and 2 were found to have distorted tetrahedral geometry around the Ag(I). The spectroscopic properties of the studied complexes have been calculated using the same level of theory. The Infrared vibrational frequencies of the COO stretches confirmed that the OAC is monodentate in 1 while the TFA is bidentate in 2. The calculated polarizability (α0) and HOMO–LUMO energy gap (ΔE) values indicated that 1 has higher NLO activity than 2. The electronic spectra of these complexes are calculated using the TD-DFT calculations. The calculated 1H NMR chemical shift values using GIAO approach showed good correlations with the experimental data. The interaction energies using the second order perturbation theory have been used to study the different intramolecular charge transfer interactions in the studied complexes. The NBO calculations indicated that both the AgO bonds are almost identical in 2 but not in 1.

The optimized molecular structure of complexes 1 and 2.Figure optionsDownload as PowerPoint slide