Anantharaman, M R; Saravanan, S; Joseph, Mathai C; Venkitachalam, S; Prabhakaran, P V(Elsevier, January 11, 2006)
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Abstract:
Polyaniline is chemically synthesised and doped with camphor sulphonic acid. FTIR studies carried out on these samples indicate that
the aromatic rings are retained after polymerisation. The percentage of crystallinity for polyaniline doped with camphor sulphonic acid
has been estimated from the X-ray diffraction studies and is around 56% with respect to polyaniline emeraldine base. The change in
dielectric permittivity with respect to temperature and frequency is explained on the basis of interfacial polarisation. AC conductivity is
evaluated from the observed dielectric permittivity. The values of AC and DC conductivity and activation energy are calculated. The
activation energy values suggested that the hopping conduction is the prominent conduction mechanism in this system.
Description:
Journal of Physics and Chemistry of Solids 67 (2006) 1496–1501
Kumar, G A; Thomas, J; Unnikrishnan, N V; Nampoori, V P N; Vallabhan, C P G(Elsevier, 2001)
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Abstract:
Optical absorption and emission spectral studies of various phthalocyanine molecules, viz., LaPc, NdPc, SmPc, EuPc, CuPc and ZnPc in a polymer matrix of cyano acrylate are reported for the first time. All the absorption spectra show an intense B band (Soret) in the UV region followed by a weaker Q band in the visible region. The positions of the Q and B bands are found to have dependence on the metallic substitution. Values of the important spectral parameters, viz., molar extinction coefficient (ϵ), oscillator strength (f), radiative transition rate and decay time of the excited singlet state are also presented and compared with other solid matrices. The recorded fluorescence spectrum shows two broad emission bands in the case of NdPc, whereas for ZnPc only a very weak band is observed. The absence of emission bands for the other metallated phthalocyanines is attributed to increased spin orbit interaction and intersystem crossing.