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51.
A method is presented for an accurate numerical determination of eigenvalues of real symmetric para-p diagonal matrices. The method takes advantage of the band structure to break up the matrix intop ×p blocks and performing algebraic operations including inversions on these blocks only, no matter what the size of the matrix is. The eigenvalues are determined independently one at a time. Thus any error in the determination of one eigenvalue does not affect the other eigenvalues. The method is ideally suited for the Schrödinger eigen alue problem of the anharmonic potentials, which is taken up in the following paper. 相似文献
52.
53.
Hyperfine Interactions - Mössbauer spectroscopy has been remarkably useful in understanding several properties of the mixed oxides. The investigations relating to spin arrangements form an... 相似文献
54.
55.
Edward W. Abel Suresh K. Bhargava Maqbool M. Bhatti Muhammed A. Mazid Keith G. Orrell Vladimir Šik Michael B. Hursthouse K.M. Abdul Malik 《Journal of organometallic chemistry》1983,250(1):373-382
The dinuclear complexes [Re2X2(CO)6(RCH2EECH2R)] (X = Cl or Br, R = Ph or Me3Si, E = S or Se) have been prepared and characterized. A variable temperature 1H NMR study on these complexes demonstrated the pyramidal atomic inversion process at the coordinated sulphur and selenium atoms. Total band-shape fittings were used to yield activation parameters for the rate process, in which the two sulphur or selenium atoms undergo synchronous or correlated inversion. 相似文献
56.
Suman Mehrotra Jayanti P. Barthwal Bhagwan R. Pandey Krishna P. Bhargava Surendra S. Parmar 《Journal of heterocyclic chemistry》1980,17(6):1213-1214
Several 2-aryl substituted thiosemicarbazido-4-methyl-6-methoxyquinolines and 2-aryl substituted semi-carbazido 4-methyl-6-methoxyquinolines were synthesized and evaluated for their antimalarial activity in mice infected with Plasmodium berghei. Two of these substituted quinolines were found to exhibit 50% clearance in a dose of 500 mg./kg. administered intraperitoneally for 5 days. 相似文献
57.
Bhargava S Hou J Parvez M Sorensen TS 《Journal of the American Chemical Society》2005,127(11):3704-3705
The first X-ray crystal structures of two different bicyclo[1.1.0]butanones show a very long transannular bond of 1.69 A and a large carbonyl pyramidal distortion of 0.26 A out of the plane of the three carbons. These features are those expected of molecules with a hybrid cyclopropanone-oxyallyl structure, and these structures differ markedly from those of the parent bicyclo[1.1.0]butane skeleton. 相似文献
58.
Om P. Bhargava 《Talanta》1979,26(2):146-148
A method for the complexometric determination of aluminium in iron ore, sinter, concentrates and agglomerates encountered in international trade is described. The sample is fused in a zirconium crucible with a mixed flux of sodium carbonate and sodium peroxide. The fused mass is completely soluble in hydrochloric acid. The R2O3 oxides are then precipitated with ammonia and redissolved in hydrochloric acid. Elements such as iron, titanium and zirconium are separated from aluminium by solvent extraction with cupferron and chloroform. After removal of traces of organic matter from the aqueous phase, the solution is treated with an excess of EDTA, which is then back-titrated with zinc solution (Xylenol Orange as indicator). Addition of ammonium fluoride then releases EDTA equivalent to the aluminium and this is titrated with zinc solution. The method is rapid. The precision and accuracy are excellent, and the results comparable with those obtained by the referee method. 相似文献
59.
The floating spherical Gaussian orbital (FSGO ) method has been used to study the equilibrium geometries and electronic structures of some hydrogen-bridged systems containing lithium, beryllium, boron, and carbon. The predicted geometries are in good agreement with other theoretical estimates. The binding energies for these hydrogen-bridged systems are estimated and discussed. The FSGO total energies (EFSGO ), for all systems studied here, are found to be well correlated to nuclear–nuclear repulsion (Vnn) and nuclear–electron attraction (Vne) terms by a relation of the type EFSGO =\documentclass{article}\pagestyle{empty}\begin{document}$ {\textstyle{3 \over 7}} $\end{document} (2 Vnn + Vne). 相似文献
60.
N. K. Ray S. P. Mehandru Shobha Bhargava 《International journal of quantum chemistry》1978,13(4):529-536
The floating spherical Gaussian orbital method has been used to study the equilibrium geometries and electronic structures of some organometallic systems like LiCH3, HBeCH3, and CH3BeCH3. The predicted geometries are in good agreement with other theoretical estimates and available experimental results. Electron transfer values from carbon to metal atom and bond energies of Li? C and Be? C bonds are estimated and discussed. The wave functions obtained here have also been used to predict the electron momentum distributions and Compton profiles for LiCH3, HBeCH3, and CH3BeCH3. 相似文献