Proceedings of the Indian Academy of Sciences - Section A

Sudersanan, M.; Sundaram, A.

doi: 10.1007/BF03047107pmid: N/A

The methods available for the determination of the stability constants of non-extractable complexes by solvent extraction are reviewed. The method proposed by Connick and McVey is valid only when no complexes of the auxiliary-ligand exist in the aqueous phase. This is applicable only at very low concentrations of the auxiliary-ligand. Hence, the stability constants calculated by this method decrease with increasing concentration and approach the theoretical values only at low concentrations of the auxiliary-ligand. It is essential, therefore, to apply the rigorous method incorporating the constants for the metal-auxiliary-ligand to calculate the stability constants which are independent of the changes in the experimental conditions. This is illustrated by few typical calculations.

Bhargava, B.; Rangarajan, G.

doi: 10.1007/BF03047108pmid: N/A

Conjugacy of variations in the period range 2 to 24 hours has been examined from coherence spectra of horizontal intensity at stations which are conjugate or nearly conjugate and stations which are in similar dipole latitudes but are not conjugate. The coherence spectra computed for stations located in the auroral zone, on the equatorial side of auroral zone and at low-middle latitudes suggest that, so far as the principal lines in the spectra corresponding to 24, 12 and 8 hours are concerned,magnetic conjugacy is confined to disturbed periods and to stations in the auroral and subauroral zones. In the continuum spectrum, however, the percentages of estimates, for which coherences are statistically significant, are very high for conjugate stations in the auroral zone but decrease progressively for pairs in the equator side of the auroral zone and lower latitudes.

Ramachandran, G.

doi: 10.1007/BF03047109pmid: N/A

Goyal, S.

doi: 10.1007/BF03047110pmid: N/A

In this paper, we evaluate four finite integrals involving the products of Jacobi polynomials, Associated Legendre functions and Fox’s H-function. Since the H-function is one of the most general functions known so far, our integrals yield various interesting integrals, on specializing the parameters of the H-function. Thus we find here the integrals involving the products of Jacobi polynomials, Associated Legendre functions and Meijer’s G-function.

Jagannadham, A.; Venkateswarlu, Putcha

doi: 10.1007/BF03047111pmid: N/A

Electron paramagnetic resonance (EPR) of divalent manganese ion has been studied at 9.5 KMc/sec. These studies reveal that Mn2+ ion substitutes at a β-Cs+ site and gets associated with a vacancy at a neighbouring β-Cs+ site in the aft-plane. Thez-axis of this ββ complex makes an angle of 25° with the crystallographicb-axis. The spectra observed have been described by the spin-Hamiltonian for Mn2+ in rhombic crystalline field. The temperature dependence of the parameters D and E has been studied in the range 293°–77° K. The spectra for the observed complex along its three-principal axes have been analysed using second order perturbation equations. The spin-Hamiltonian parameters obtained from the spectra taken at room temperature are: $$\begin{gathered} g_z = 2 \cdot 000 \pm 0 \cdot 003, g_x = 2 \cdot 015 \pm 0 \cdot 003, g_y = 2 \cdot 000 \pm 0 \cdot 003; \hfill \\ A_z = - 93 \pm 1, A_x = - 91 \pm 1, and A_y = - 91 \pm 1 G; \hfill \\ D = - 941 \pm 3 and E = - 14 \pm 4 G; \hfill \\ b^\circ _4 = \left( {0 \cdot 0} \right), b_4 ^2 = \left( {13} \right), and b_4 ^4 = - 77 \pm 5 G \hfill \\ \end{gathered} $$