Nampoori, V P N; Litty, Irimpan; Dann, V J; Krishnan, B; Deepthy, A; Radhakrishnan, P(Laser Physics, 2008)
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Abstract:
Light-scattering experiments gained prominence as potential applications of quantum optics, nonlinear
optics, and photon localization. The possibility of the realization of lasing action in random media has
created much interest in the study of the coherent structure of the backscattered light from disordered media.
Backscattering (BS) studies are carried out to analyze the possibilities of photon localization in colloidal silica.
The scattering enhancement is best associated with the density of the scatterers. The width of the BS cone and,
hence, the mean-free path is related to the concentration of the medium. The dependence of the photon wavelength
on the possible characteristics of the scattering is presented.
Bessy Raj, B N; Dr.Prathapachandra Kurup,M R(Cochin University of Science and Technology, February , 2009)
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Abstract:
The present work deals with the complexation of Schiff
bases of aroylhydrazines with various transition metal ions. The hydrazone
systems selected for study have long 7I:-delocalized chain in the ligand molecule
itself, which get intensified due to metal-to-ligand or ligand-to-metal charge
transfer excitations upon coordination. Complexation with metal ions like copper,
nickel, cobalt, manganese, iron, zinc and cadmium are tried. Various spectral
techniques are employed for characterization. The structures of some complexes
have been well established by single crystal X-ray diffraction studies. The nonIinaer
optical studies of the ligands and complexes synthesized have been studied
by hyper-Rayleigh scattering technique.The work is presented in seven chapters and the last one deals with
summary and conclusion. One of the hydrazone system selected for study proved
that it could give rise to polymeric metal complexes. Some of the copper, nickel,
zinc and cadmium complexes showed non-linear optical activity. The NLO
studies of manganese and iron showed negative result, may be due to the inversion
centre of symmetry within the molecular lattice.
Description:
Department of Applied Chemistry,
Cochin University of Science and Technology