NOPR Collection:

EPR and optical absorption spectra of Cu(II) doped zinc potassium phosphate hexahydrate

Tue, 01 Jun 1999 00:00:00 GMT

Title: EPR and optical absorption spectra of Cu(II) doped zinc potassium phosphate hexahydrate Authors: N, Madhu; Chandrasekhar, A V; Reddy, B J; Reddy, Y P; Ravikumar, R V S S N; Rao, P S Abstract: EPR and optical absorption spectra of copper-doped zinc potassium phosphate hexahydrate (ZPPH) are recorded both at room temperature and liquid nitrogen temperature. Both, EPR and optical spectra are characteristic of Cu(II) ion in rhombically distorted octahedral symmetry. Spin-Hamiltonian and bonding parameters have also been evaluated as follows: g₁,=2.372; g₂=2.188; g₃=2.032; A₁, =78×10^-4 cm^-1; A₂, =48×10^-4 cm^-1; A₃, =63×10^-4 cm^-1,
²=0.55 Page(s): 590-591

Charge-transfer transition energies of EDA complexes between o-chloranil and a series of phenols: A correction with AMI results

Tue, 01 Jun 1999 00:00:00 GMT

Title: Charge-transfer transition energies of EDA complexes between o-chloranil and a series of phenols: A correction with AMI results Authors: Datta, Kakali; Mukherjee, A K; Banerjee, M; Seal, B K Abstract: The ground state geometries of electron donor-acceptor (EDA) complexes between o-chloranil and a series of phenols have been optimised by AMI method, adopting a ‘super molecule’ model for each DA adduct. Their S₁← S₀ transition energies are calculated through configuration interaction. The calculated electronic charge distributions and dipole moments in the ground and excited states of each EDA complex show that S₁← S₀transition corresponds to the transfer of one electron to o - chloranil from the phenol moiety; the theoretical transition energies, after correction for salvation, have been found to agree fairly well with the experimentally reported values of charge transfer transition energies of the EDA complexes. Page(s): 585-586

Physicochemical studies of 2-propanol in some micellar solutions

Tue, 01 Jun 1999 00:00:00 GMT

Title: Physicochemical studies of 2-propanol in some micellar solutions Authors: Yadav, Satyender K; Kumar, Ashok; Yadav, O P` Abstract: Conductance values of sodium dodecyl sulphate and dodecyl trimethyl ammonium bromide have been measured in aqueous and 2-propanol+water solutions. The measurements are carried out at 298.15, 308.15 and 318.15 K. From conductivity data the values of critical micelle concentration and counterion association constant () are determined. The observed thermodynamic data reveals that micellisation process is favoured both energetically as well as by entropy gain. ¹H NMR data of solutions indicate that whereas 2-propanol is solubilised in the interior of SDS micelles, the penetration of 2-propanol into DTAB micelles is comparatively weak. Page(s): 529-532

Preparation and characterisation of some lanthanide complexes involving a heterocyclic β – diketone

Tue, 01 Jun 1999 00:00:00 GMT

Title: Preparation and characterisation of some lanthanide complexes involving a heterocyclic β – diketone Authors: Patel, P R; Thaker, B T; Zele, S Abstract: The complexes of the composition [Ln(PMVP)₃.H₂O.C₂H₅OH].H₂O(where Ln = trivalent lanthanides such as La, Ce, Nd, Sm, Gd, Dy, Er and PMVP = 1-phenyl-3-methyl-4-valeroyl-2-pyrazoline-5-one) have been synthesised. These have been characterised on the basis of elemental analyses, conductance, magnetic measurement, electronic, IR, NMR, TGA, and DTA studies. IR spectra and thermograms show the presence of both coordinated and non-coordinated water molecules. The oscillator strengths of the f - f transitions have been calculated and discussed. The complexes appear to accept one solvent molecule (C₂H₅OOH) and become eight coordinated as revealed by the NMR spectra. Page(s): 563-567