Electronic structure and nature of the bands in electronic absorption spectra of stable phenoxyl radicals of indophenoxyl and galvinoxyl

1988 ◽  
Vol 23 (6) ◽  
pp. 682-685 ◽  
Author(s):  
L. S. Degtyarev
2017 ◽  
Vol 5 (2) ◽  
pp. 95-102
Author(s):  
Tatyana Yegorova ◽  
Andriy Kysil ◽  
Igor Levkov ◽  
Andrei Ilchenko ◽  
Zoia Voitenko

The electronic structure and absorption spectra of cyanine dyes – tetrazoloisoindole derivatives and triazoloisoindole were calculated. It was shown that these dyes, in terms of their electronic structure, are trimethine cyanine, although formally they are monomethine cyanine. The electron donation of the tetrazoloisoindole and triazoloisoindole residues was determined on the Ilchenko scale, which allows them to quantitatively quantify their Bruker basicity in comparison with the most known heterocyclic end groups of cyanine dyes.


2018 ◽  
Vol 9 (4) ◽  
pp. 287-302
Author(s):  
Shimaa Abdel Halim

A new bis-spiropipridinon/pyrazole compound and some of its derivatives are characterized in terms of several theoretical parameters such as density of states (DOS), molecular electrostatic potentials (MEPs), non-linear optical (NLO) properties and electrophilicity. The electronic structure and nonlinear optical properties of the studied compounds 1-5 are investigated theoretically at the DFT-B3LYP/6-311G(d,p) level of theory. The effect of substituents of different strengths on the geometry and energetic are analyzed and discussed. The static dipole moment (µ), polarizability (α), anisotropy polarizability (Δα), and first order hyperpolarizability (βtot), are parameters for NLO of the studied compounds have been calculated at the same level of theory and compared with the prototype para-nitro-aniline (PNA). The electronic absorption spectra of the studied compounds are recorded in the UV-VIS region, in both ethanol and dioxane solvents. The theoretical spectra computed at a new hybrid exchange-correlation functional using the Coulomb-attenuating method (CAM-B3LYP) at the 6-311G(d,p) bases set in gas phase and with the polarizable continuum model (PCM) in dioxane and ethanol indicate a good agreement with the observed spectra. The antimicrobial activity for studied compounds was investigated. The antimicrobial activity results revealed that compound 4 has a good potency against Gram positive bacteria (E. coli) and Gram negative bacteria (P. vulgaris) in comparison with doxymycin standard. The structure activity relationship SAR has been studied for the studied compounds by DFT calculations, moreover, confirmed practical antimicrobial  activity results.


1986 ◽  
Vol 40 (4) ◽  
pp. 556-562 ◽  
Author(s):  
Rifaat Hilal ◽  
Sulaiman Basahel ◽  
Saadullah Aziz

The electronic absorption spectra of a number of N-acylimidazoles have been investigated with special emphasis on the type and extent of interaction across the carbonyl group. Quantitative discussion of substituent and solvent effects is presented, based on the results of MO Computation and energy partitioning analysis. The results of the present analysis enabled a quantitative definition of the classical and frequently used terminology of cross- and linear conjugation.


2020 ◽  
Vol 22 (41) ◽  
pp. 23886-23898
Author(s):  
Jhonathan Rosa de Souza ◽  
Matheus Morato F. de Moraes ◽  
Yuri Alexandre Aoto ◽  
Paula Homem-de-Mello

One must be skeptical about the reference chosen to benchmark electronic structure calculations, such as DFT functionals and active spaces for multireference calculations.


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