Junaid, Bushiri M; Antony, C J; Aatiq, A; Yohannan Panicker, C; Hema, Tresa Varghese; Manojkumar, T K(Elsevier, November 15, 2010)
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Abstract:
FT-Raman and FT-IR spectra of ASnFe(PO4)3 [A=Na2, Ca, Cd] were recorded and analyzed. The bands
were assigned in terms of the vibrational group frequencies of SnO6 octahedral and PO4 tetrahedral. The
spectral analysis shows that the symmetry of corner shared octahedral (SnO6) and the tetrahedral (PO4)
are lowered from their free ion symmetry state. The presence of Fe3+ ions disrupts the S–N–O–S–N chain
in the structure. This causes distortion of SnO6 and PO4 in the structure of all the compounds. Also it is
seen that there are two distinct PO4 tetrahedra of different P–O bond lengths. One of these tetrahedra
is linearly distorted in all the title compounds. The PO4 frequencies and bond lengths are calculated
theoretically and are in agreement with the experimental values. The presence of PO4 polyanion in the
structure can reduce the redox energy and hence reduce the metal oxygen covalency strength in the
structure
Poly(6-tert-butyl-3,4-dihydro-2H-1,3-benzoxazine) was synthesized by
thermally activated cationic ring opening polymerization. The structure of the
polymer was confirmed by spectral and thermal studies. The highest occupied
molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) were
estimated using cyclic voltammetry and optical absorption. Modulated photocurrent
measurement technique was employed to study the spectral and field dependence of
photocurrent. Photocurrent of the order of 1.5 micro A/m2 was obtained for polymer at a
biasing electric field of 40 V/mico m.
Prathapachandra Kurup, M R; Sheena Mary, Y; Raju, K; Yohannan Panicker, C; Neema, Ani Mangalam; Hema, Tresa Varghese; Sheeja, S R(Elsevier, March 16, 2010)
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Abstract:
FT-IR spectrum of quinoline-2-carbaldehyde benzoyl hydrazone (HQb H2O) was recorded and analyzed.
The synthesis and crystal structure data are also described. The vibrational wavenumbers were examined
theoretically using the Gaussian03 package of programs using HF/6-31G(d) and B3LYP/6-31G(d) levels of
theory. The data obtained from vibrational wavenumber calculations are used to assign vibrational bands
obtained in infrared spectroscopy of the studied molecule. The first hyperpolarizability, infrared intensities
and Raman activities are reported. The calculated first hyperpolarizability is comparable with the
reported values of similar derivatives and is an attractive object for future studies of non-linear optics.
The geometrical parameters of the title compound obtained from XRD studies are in agreement with
the calculated values. The changes in the CAN bond lengths suggest an extended p-electron delocalization
over quinoline and hydrazone moieties which is responsible for the non-linearity of the molecule
Description:
Journal of Molecular Structure 973 (2010) 36–46 http://dx.doi.org/10.1016/j.molstruc.2010.03.016