Theoretical Studies of Molecular Structures, Infrared Spectra, NBO and NLO Properties of Some Novel 5-arylazo-6-hydroxy-4-phenyl-3-cyano-2-pyridone Dyes

Abstract

The optimized geometrical structures, infrared spectra, molecular electrostatic potential, natural bond orbital and nonlinear optical properties of 5-phenylazo-6-hydroxy-4-phenyl-3-cyano-2-pyridoine (1) and 5-(4-bromophenylazo)-6-hydroxy-4-phenyl-3-cyano-2-pyridoine (2) dyes with a detailed study on the azo-hydrazone tautomerism in the ground state have been investigated by density functional theory using B3LYP functional with 6-31G(d,p) basis set. Vibrational modes are assigned with the help of vibrational energy distribution analysis program. Highest occupied molecular orbital and lowest unoccupied molecular orbital energies of the (1) and (2) compounds with azo and hydrazone forms were calculated with the same method and basis set. Molecular parameters like global hardness (η), global softness (σ) and electronegativity (χ) were calculated with the results obtained from the highest occupied and lowest unoccupied molecular orbital energies. Nonlinear optical parameters (mean polarizability ( α ), the anisotropy of the polarizability ( ∆α ) and the mean first-order hyperpolarizability ( β )) of the title compounds were investigated theoretically. The atomic charges, electronic exchange interaction, and charge delocalization of the molecules have been studied by natural bond orbital analysis.

Spectroscopic, Hirshfeld Surface Analysis, and Molecular Docking Studies on Potent Anti‐Inflammatory and Analgesic Activity Methyl 3‐methyl‐2‐((pyridin‐2‐ylcarbonyl)amino)Benzoate

“…The calculated C4−N5 and N5−C6 bond distances were 1.333 and 1.338 Å for the B3LYP/6‐311+G(d,p) method, whereas these bond distances for the PBEPBE/6‐311+G(d,p) method were 1.341 and 1.346 Å. As shown in Table , the calculated values with the B3LYP and PBEPBE methods with the 6‐311+G(d,p) basis set correspond well to those within the literature . The longest bond length of all bonds in the molecule was found to belong to the C6−C7 bond.…”

“…As shown in Table 1, the calculated values with the B3LYP and PBEPBE methods with the 6-311 + G(d,p) basis set correspond well to those within the literature. [26] The longest bond length of all bonds in the molecule was found to belong to the C6À C7 bond. The bond distances C7À O8 and C17À O18 are the smallest in the title molecule.…”

Theoretical Investigation on the Molecular Structure, Electronic, Spectroscopic Studies and Nonlinear Optical Properties of 5-bromo-1-(2-cyano-pyridin-4-yl)-1H-indazole-3-carboxylic acid diethylamide: a DFT and TD-DFT Study

“…The heteroaromatic organic compounds commonly exhibit multiple weak bands in the region 3100-3000 cm −1 , which is the characteristic region for the ready identification of C-H stretching vibrations and these vibrations are not found to be affected due to the nature and position of the substituent [39,40]. In the present work, the vibrations (ν 1-4 and ν 5-6) in Table II Similarly, the experimental FT-IR spectra of the title compound are found at 3436.79 and 3102.34 cm −1 [9].…”

Linear and NLO Properties of Functional Group and Position Isomers of Azo and Azomethine: Comparative Photophysical‐Electrochemical Properties, Z‐Scan and DFT Studies

“…Quantum mechanics are also widely used to investigate the molecules at the molecular level to give useful guidelines in the design of organic NLOphoric materials. [17,[45][46][47][48][49][50][51][52][53][54] In the present work, we have investigated for the first time the effect of functional group isomers and position isomers of azo and azomethine, and their effect on linear and non-linear optical properties. For this purpose, we have selected three reported molecules [55,56] VA-1,VI (1-2) and are synthesized as previously reported by our group in same manner we have synthesized one azo analog VA-2 (see Scheme 1).…”