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FT-IR (in solid state and solution), FT-Raman, UV and 1H, 13C NMR spectra of p-methoxybenzoic (p-anisic) acid and lithium, sodium, potassium, rubidium and caesium p-methoxybenzoates (p-anisates) were registered, assigned and analyzed. The structures of anisic acid and Li, Na and K p-anisates were optimised at the B3LYP/6-311++G** level. The IR spectra and NPA, ChelpG and MK atomic charges were calculated. The effect of metal ions on the electronic charge distribution in ligand was discussed. [ABSTRACT FROM AUTHOR]

Abstract: The influence of lithium, sodium, potassium, rubidium and cesium on the electronic system of the 2-aminobenzoic acid was studied by the methods of molecular spectroscopy. The vibrational (FT-IR, FT-Raman) and NMR (1H and 13C) spectra for 2-aminobenzoic acid and its alkali metal salts were recorded. The assignment of vibrational spectra was done on the basis of literature data, theoretical calculations and our previous experience. Characteristic shifts of bands and changes in intensities of bands along the metal series were observed. The changes of chemical shifts of protons (1H NMR) and carbons (13C NMR) in the series of studied alkali metal 2-aminobenzoates were observed too. Optimized geometrical structures of studied compounds were calculated by B3LYP method using 6-311++G∗∗ basis set. Geometric aromaticity indices, dipole moments and energies were also calculated. The theoretical wavenumbers and intensities of IR and Raman spectra were obtained. The calculated parameters were compared to experimental characteristic of studied compounds. [Copyright &y& Elsevier]

Abstract: The influence of nitro-substituent in ortho, meta and para positions as well as lithium, sodium, potassium, rubidium and cesium on the electronic system of aromatic ring and the distribution of electronic charge in carboxylic group of the nitrobenzoates were estimated. Optimized geometrical structures were calculated (B3LYP/6-311++G∗∗). To make quantitative evaluation of aromaticity of studied molecules the geometric (AJ, BAC, I6 and HOMA) as well as magnetic (NICS) aromaticity indices were calculated. Electronic charge distribution was also examined by molecular spectroscopic study, which may be the source of quality criterion for aromaticity. Experimental and theoretical FT-IR, FT-Raman and NMR (1H and 13C) spectra of the title compounds were analyzed. The calculated parameters were compared to experimental characteristics of these molecules. [Copyright &y& Elsevier]

The FT-IR, FT-Raman and 1H and 13C NMR spectra of lithium, sodium, potassium, rubidium and caesium picolinates were recorded, assigned and compared in the Li → Na → K → Rb → Cs series and analysed. Experimental, vibrational and NMR spectra were interpreted with the aid of calculated data from density functional theory at the B3PW91/6–311 ++ G** level. Distance, angles and dipole moments and also aromaticity indices (HOMA, EN, GEO, I6) for the optimized structures of picolinic acid and sodium picolinate were calculated. Comparison of theoretical and experimental (x-ray) data and the application of Bader's theory enabled us to evaluate the intramolecular interactions in picolinic acid. Also, the influence of the carboxylic anion structure and the nature of metal–ligand bonding on the electronic charge distribution in the aromatic ring was investigated. The degree of perturbation in the electronic system of the ligand under the influence of metal in the Li → Cs series was investigated with the use of statistical methods (principal component analysis) and calculated aromaticity indices. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]