Electrostatic interactions provide a primary connection between a protein's three-dimensional structure and its function. Infrared probes are useful because vibrational frequencies of certain chemical groups, such as nitriles, are linearly sensitive to local electrostatic field and can serve as a molecular electric field meter. IR spectroscopy has been used to study electrostatic changes or flu...

The FT-IR and Raman spectra of 4-Chloro-2-Fluroaniline (4C2FA) were measured. The fundamental vibrational frequencies and intensity of vibrational bands were evaluated using density functional theory (DFT) and standard B3LYP/6-311+G** basis set combination. The vibrational spectra were interpreted, with the aid of normal coordinate analysis based on a scaled quantum mechanical (SQM) force field...

Raman and FTIR spectra of 6-fluoronicotinc acid (6FNA) have been analyzed using ab-initio and Density Functional Theory (DFT) calculations. Four stable structures of 6fluoronicotinc acid have been found, the structures differ in orientation of COOH with respect to the nitrogen atom. The optimized geometries, structural parameters, harmonic vibrational wave number and intensity of the vibrationa...

FT-Raman and FT-IR spectra of 5-methyl-2-(p-fluorophenyl)benzoxazole were recorded and analysed. The vibrational frequencies of the compound have been computed using the Hartree-Fock/6-31G* basis and compared with the experimental values.

self-association of alcohols; including ethanol, methanol, cyclopentanol and octanol in separate mixtures with inert solvents have been studied using ft-ir spectroscopy. except for the band at 3640 cm–1 in the ir spectrum of the alcohols which is due to the monomer species, the presence of other bands in the region of stretching vibrational frequencies of oh (3100-3700 cm–1) are attributed to t...

The Molecular structure, conformational stability and vibrational frequencies of succinonitrile NCCH2CH2CN have been investigated with ab initio and density functional theory (DFT) methods implementing the standard 6-311++G* basis set. The potential energy surfaces (PES) have been explored at DFT-B3LYP, HF and MP2 levels of theory. In agreements with previous experimental results, the molecule ...

Molecular structure and vibrational frequencies of the novel surface enolic species intermediate on Ag/Al2O3 have been investigated by means of density functional theory (DFT) calculations and in situ infrared spectroscopy. The geometrical structures and vibrational frequencies were obtained at the B3P86 levels of DFT and compared with the corresponding experimental values. Theoretical calculat...

in the present work, dft calculations are employed to obtain the optimized structures of 4-acyl pyrazolone tautomers (19 tautomers) using b3lyp/6-311++g** calculations. inaddition, molecular parameters, ir frequencies and relative energies are extracted for alltautomers. the existence of aromatic ring, keto tautomer (versus enol tautomer), n-h bond(versus c-h bond) and c=n double bond (versus n...

Cavity ringdown spectra of the near IR Ã2A′ − X̃2A′′ electronic transition of acetyl peroxy radical and its perdeutero analogue are reported. The electronic origin for the CH3C(O)O2 is observed at 5582.5(5) cm−1. Extensive ab initio calculations have been carried out to predict frequencies and help assign the electronic origin, observed vibrational hot bands and several à state vibrational frequ...

BACKGROUND 2-amino pyridine derivatives have attracted considerable interest because they are useful precursors for the synthesis of a variety of heterocyclic compounds possessing a medicinal value. In this work we aim to study both structural and electronic as well as high quality vibrational spectra for 2-amino-3-methylpyridine (2A3MP) and 2-amino-4-methylpyridine (2A4MP). RESULTS Møller-Pl...