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951.
On the sign of magnetic anisotropy and electronic structure of ferrous ammonium sulphate hexahydrate
The magnetic anisotropies and principal susceptibilities of ferrous ammonium sulphate hexahydrate are investigated to remove the existing discrepancies in the sign of its molecular magnetic anisotropy and the nature of ligand field and electronic structure. 相似文献
952.
An expression for the kinetic energy part of the vibration-torsion-rotation Hamiltonian of an asymmetric top molecule containing a C3v internal rotor has been derived. The terms for various interactions in the molecule, viz. Coriolis interaction between rotation (both overall and internal rotation) and vibration, centrifugal distortion and anharmonicity of molecular vibrations induced by the internal, and overall rotation of the molecule, have been formulated. For a planar molecule with Cs symmetry we have obtained the vibrationally averaged rotation-internal rotation Hamiltonian. Diagonalization of this Hamiltonian for a particular vibrational state will yield the rotation-internal rotation energy levels and hence the transition frequencies. These data will be useful for analysis of high-resolution infrared spectra obtained by laser or Fourier transform spectroscopy of nonrigid molecules with internal rotor. We also present a set of quartic centrifugal distortion coefficients associated with rotation and internal rotation. These data will be helpful for evaluation of vibrational potential constants of the orthorhombic asymmetric top molecules. 相似文献
953.
Novel ditopic receptors for guanosine have been prepared and characterised. Their association constants with a lipophilic guanosine derivative are somewhat smaller than the expected values for a guanosine-cytidine base pair, but remain in a useful range for building supramolecular structures. 相似文献
954.
Summary The Indian summer monsoon rainfall data for eleven pairs of stations have been subjected to maximum entropy spectral analysis
(MESA). The results of the analysis appear to indicate Moon's long-period (18.6y) nodal tidal influence on rainfall. The 10–11
y solar cycle term in rainfall appears to be split up into two components in the spectral results of almost all the stations,
as a result of spectral analysis. 相似文献
955.
A.K. Mitra 《Applied mathematics and computation》1984,15(4):275-281
A simple numerical scheme has been developed for the solution of the eigenvalue problem arising in a patch formation model given by Del Grosso et al. [1]. The scheme is based on finding bounds which separate the eigenvalues. The exact eigenvalues are obtained by solving an algebraic equation given by the corresponding regular Frobenius series solution. At the same time eigenfunctions may also be obtained from this series solution. 相似文献
956.
957.
Average magnetisation between 2 and 20 K and 10 and 50 kOe of two typical high-spin manganese(III) porphyrins, namely TPPMnCI and TPPMnCl(py), is reported for the first time. The results have been analysed in terms of spin hamiltonian formalism including both the crystal field and magnetic exchange. 相似文献
958.
Amarendra Patra Alok K. Mitra Arundhati Ghosh Prabir K. Mukhopadhyay 《Magnetic resonance in chemistry : MRC》1981,16(1):65-67
Carbon-13 NMR spectral studies of tembamide (1) and aegeline (2), constituents of Fagara hyemalis and Aegle marmelos respectively, and a series of their structurally related amides (3–13) have been carried out. The assignment of the resonances of two related dimers are also reported. The assignment of the various resonances were made by considering the changes in chemical shifts produced by the change of substituents and also by using 1, 13 and a related compound as model compounds. 相似文献
959.
Amarendra Patra Alok K. Mitra Swapna Biswas Chitra Das Gupta Tapan K. Chatterjee K. Basu A. K. Barua 《Magnetic resonance in chemistry : MRC》1981,17(4):301-302
Carbon-13 signal assignments of the labdane diterpenoids phlogantholide-A, its diacetate and isophlogantholide-A are reported. The assignments of the 13C NMR signals of 14-deoxyandrographolide and its diacetate, made earlier, have now been confirmed by lanthanide shift studies on the former and also by 13C spectral studies on anhydroandrographolide diacetate and 14-deoxy-11,12-didehydroandrographolide diacetate. 相似文献
960.