The calculated quantum chemical parameters are, ,, and those parameters that give valuable information about the reactive behavior such as chemical potential, global hardness ( ), and the softness ( ). In addition, the gauge-invariant-atomic orbital (GIAO) 13C and 1H chemical shifts calculations of the title compounds were calculated by using B3LYP/6-31G** basis set. Natural bond orbital (NBO) analysis of the title molecules was also carried out. In this study, we recorded FTIR and FT-Raman spectra and calculated the vibrational frequencies of O-Anisic acid and Anisic acid in the ground state to distinguish fundamentals from experimental vibrational frequencies and geometric parameters using DFT/B3LYP (Becke3-Lee-yang-Parr) method. In the SQM approach, the systematic errors of the computed harmonic force field are corrected by a few scale factors which were found to be well transferable between chemically related molecules. A significant advent in this area was made by the scaled quantum mechanical (SQM) force field method. Quantum chemical computational methods have proven to be an essential tool for interpretations and prediction of vibrational spectra. The vibrational assignments of the compounds can be proposed on the basis of the wavenumber agreement between the computed harmonics and the observed fundamentals. O-Anisic acid is used in organic synthesis and antiseptic disinfectant. Anisic acid and its derivatives are also widely used in chemical reaction as intermediates to obtain target materials such as dyes, pharmaceuticals, perfumes, photoinitiators, and agrochemicals. Anisic acid is a part of cresol class antiseptic compounds. They are typically used in pharmaceutical and perfumery industry.Īnisic acid or methoxy benzoic acid is an organic compound which is a carboxylic acid. Benzoic acid derivatives substituted by hydroxyl group or ether containing oxygen atom have active bacteriostatic and fragrant properties. In medicine, aromatic acids are employed as weak antiseptics, and their salts as carriers of specific cations. IntroductionĪromatic acids have all the properties characteristic of the carboxylic acids of the aromatic series. The 13C and 1H NMR chemical shifts of the DFA and CA molecules were calculated using the gauge-invariant-atomic orbital (GIAO) method in DMSO solution using IEF-PCM model and compared with experimental data. Comparison of simulated spectra with the experimental spectra provides important information about the ability of the computational method to describe the vibrational modes. The effects of carbonyl and methyl substitutions on the structure and vibrational frequencies have been investigated. The infrared and Raman spectra were also predicted from the calculated intensities. The vibrational spectra were interpreted, with the aid of normal coordinate analysis based on a scaled quantum mechanical force field. The fundamental vibrational frequencies and intensity of vibrational bands were evaluated using density functional theory (DFT) with standard B3LYP/6-31G** method and basis set combinations. This work deals with the vibrational spectroscopy of O-Anisic acid (OAA) and Anisic acid (AA).

Lumo and humo