V. Arjunan et al. / Spectrochimica Acta Part A 79 (2011) 486–496
495
of amino group, the very strong band in IR at 1616 cm−1 is assigned
to the –NH2 deformation mode. The other fundamental bands of
amino group are observed in the expected region [41,42] and are
presented in Tables 4 and 5. Considerable overlapping of rocking
and twisting modes with N–H vibrations occurs and is confirmed
from normal coordinate analysis. The N–H stretching vibration of
tional frequencies of the fundamental modes of the compound have
been precisely assigned and analysed and the theoretical results
were compared with the experimental vibrations. The energies of
important MO’s, absorption wavelength (ꢀmax), oscillator strength
and excitation energies of the compound were also determined
from TD-DFT method and compared with the experimental val-
ues. Thus the present investigation provides complete vibrational
assignments, structural informations and electronic properties of
the compound which may be useful to upgrade the knowledge on
benzohydrazide.
−1
hydrazide group appears at 3291 cm
ing vibration of the same is observed at 1449 and 1445 cm
and the in-plane bend-
−
1
in
the IR and Raman spectrum, respectively. This vibration is over-
lapped with the C–N in-plane bending absorptions. The strong
−1
vibrational frequency observed at 675 cm in the infrared spec-
trum is assigned to the N–H out of plane bending mode of BH. This
mode is also significantly overlapped with the C–N out of plane
bending vibrations.
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8
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9
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[
[
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