In films of the polyelectrolyte complexes of glycol chitosan (gc) with alginic acid (aa) and hyaluronic acid (ha) anomalously large dielectric dispersion was observed in the range 1 to 100 kHz above 50‡C. This was attributed to the formation of electrical double layers around the polyanion by the sodium ions inevitably present in the films.

To test this hypothesis films ofgc with carboxy methyl cellulose were prepared with different concentrations of lithium, sodium and potassium ions. The films were found to absorb much larger amounts of sodium than lithium or potassium. Dielectric measurements from −40 to 80‡C in the range 1 to 100 kHz showed anomalously large dispersion above 50‡C in films with the higher concentration of alkali ions. The dispersion could be fitted to Schwarz’s equations. The characteristics of the fit were similar to those in GC-AA and GC-HA films supporting the hypothesis that the anomalous dispersion is due to an electrical double layer formed around the polyanion by the alkali ions.

Wideline and high resolutionNMR studies have been carried out inMBBA in its isotropic, nematic and solid phases. Isotropie and nematic spectra correspond to what has been reported earlier. In the solid phase, contrary to expectations, very intense narrow signals similar to signals of the isotropic phase have been observed for the first time at temperatures close to the solid ↔ nematic phase transition temperature. This indicates rapid reorientational or translational motion in the system. X-ray results however confirm the existence of translational order. The results are interpreted as indicative of the existence of a plastic crystalline phase inMBBA.

A bimetallic nickel(II) complex with the ligand Hsalamp (2-[(4-methyl-pyridin-2-ylimino)-methyl]-phenol), having the molecular formula, Ni₂C₂₆H₂₂ N₄O₁₀Cl₂, is synthesized and characterized by elemental, UV-Vis, IR and EPR studies. The IR spectrum confirms the presence of coordinated perchlorate ion and the UV-Vis. spectrum substantiates that the geometry around the metal ion is distorted square pyramidal. In the solvent methanol, the complex undergoes dissociation indicating the nature of the complex to be 1:2 electrolyte. The single crystal EPR studies indicate that the zero-field splitting is not large and the spectra can be observed even at room temperature, not so common for a nickel(II) ion. The spin Hamiltonian parameters calculated from single crystal rotations are:g - 2.377, 2.219, 2.071 and D - 9.7, 4.2 and -13.9 mT. Optical and electron paramagnetic spectral data have been used to obtain the parametersDq,B andC.