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![Contour plots of the electron densities in the plane of three azobenzene derivatives : 2-[N-ethyl-4-[( E )-(4- nitrophenyl)azo]anilino]ethanol (Disperse Red 1:DR1) and 4-[( E )-(4-nitrophenyl)azo]aniline (Disperse Orange 3:DO3) and 2-[4-[( E )-phenylazo]phenyl]ethanol (ABOH)](profile/Benoit-Minisini/publication/260453874/figure/fig1/AS:297221384884228@1447874508674/Contour-plots-of-the-electron-densities-in-the-plane-of-three-azobenzene-derivatives.png)
Contour plots of the electron densities in the plane of three azobenzene derivatives : 2-[N-ethyl-4-[( E )-(4- nitrophenyl)azo]anilino]ethanol (Disperse Red 1:DR1) and 4-[( E )-(4-nitrophenyl)azo]aniline (Disperse Orange 3:DO3) and 2-[4-[( E )-phenylazo]phenyl]ethanol (ABOH)
Source publication
In this work we assessed the performance of the density functional theory (DFT) approach through a comparison study with the experimental Raman spectrum obtained for [4-[(E)-phenylazo]phenyl]ethanol (ABOH) in the wavenumber range 900-1800 cm-1. The assignment of the 10 most active vibrational modes have been achieved using the hybrid density functi...
Contexts in source publication
Context 1
... two bond lengths were close with values of 1.418 Å and 1.416 Å; the last value is due to the substituted phenyl. However, for DO3 and DR1 the (NO 2 )phenyl-N= bond lengths were 0.02 Å longer than the other phenyl-N= distances. The slices of the electronic density for the three different compounds in the plane of the phenyl groups are presented Fig. ...
Context 2
... that of phenyl-NO 2 . Consequently, the electronic density is higher for the phenyl-N(R 1 R 2 ) bond than for the phenyl-NO 2 bond, meaning a higher bond order, com- patible with the idea of a lower bond length. Unfortunately, we cannot draw a similar conclusion con- cerning the azo bonds because the discrepancies in the qualitative results in Fig. 5 were not visible even for the higher density ...
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Citations
... It was shown in Ref. [29] that a B3LYP and a 6-31++G(d,p) level of theory is appropriate for vibrational analysis of azobenzene derivatives. Raman and Infra-red spectra (IR) for ADAB obtained within this level of theory are presented in Fig.3 and Fig.5 respectively, the IR spectra of AB (Fig.4) is presented as well. ...
In the present work we investigate the structural, electronic, vibrational
and molecular properties of 4-[(E)-(4-dimethylaminophenyl)azo]aniline (ADAB)
within density functional theory (DFT) using the hybrid B3LYP functional
with a 6-31++G(d,p) basis set. We consider both trans and cis con�gurations
of ADAB molecule. We present results for azobenzene (AB) as well
for comparison. The planar structures was obtained for the optimized trans
con�gurations. We �nd energy di�erence between trans and cis con�gurations
and the activation energy. We calculate the di�erence in the dipole
moments between trans and cis forms. We obtained that it is higher than
that for azobenzene by 1.5 Debye.
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