Abdul Rasheed, T M; Moosad, K P B; Nampoori, V P N; Sathianandan, K(American Chemical Society, 1987)
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Abstract:
Vibrational overtone spectra of acetophenone and benzaldehyde in the visible and near-infrared regions are studied by the
dual beam thermal lens and the conventional near-infrared absorption techniques. The observed increase in the mechanical
frequency of the aryl CH bond from that of benzene is attributed to the decrease in the aryl CH bond length caused by
the electron-withdrawing property of the substituents. Overtone spectra also demonstrate that acetophenone contains two
types of methyl CH bonds arising from the anisotropic environments created by oxygen lone pair and carbonyl P electrons.
The local-mode parameters of the two types of CH bonds are compared with those of acetone and acetaldehyde. The possible
factors influencing the methyl CH bonds in acetophenone are discussed.
Prathapachandra Kurup, M R; Suma, S; Sudarsana Kumar, M R; Siji, V L(Elsevier, February 26, 2010)
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Abstract:
Eight new transition metal complexes of benzaldehyde-N(4)–phenylsemicarbazone have been synthesized
and characterized by elemental analyses, molar conductance, electronic and infrared spectral
studies. In all the complexes, the semicarbazone is coordinated as neutral bidentate ligand. 1H NMR
spectrum of [Zn(HL)2(OAc)2] shows that there is no enolisation of the ligand in the complex. The magnetic
susceptibility measurements indicate that Cr(III), Mn(II), Fe(III), Co(II) and Cu(II) complexes are
paramagnetic and Ni(II) is diamagnetic. The EPR spectrum of [Mn(HL)2(OAc)2] in DMF solution at 77K
shows hyperfine sextet with low intensity forbidden lines lying between each of the two main hyperfine
lines. The g values calculated for the [Cu(HL)2SO4] complex in frozen DMF, indicate the presence of
unpaired electron in the dx2−y2 orbital. The metal ligand bonding parameters evaluated showed strong
in-plane bonding and in-plane bonding. The ligand and complexes were screened for their possible
antimicrobial activities.
Description:
Spectrochimica Acta Part A 76 (2010) 22–28 doi:10.1016/j.saa.2010.02.035