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161.
162.
This paper deals with the solutions of time independent Schrödinger wave equation for a two-dimensional PT-symmetric coupled quintic potential in its most general form. Employing wavefunction ansatz method, general analytic expressions for eigenvalues and eigenfunctions for first four states are obtained. Solutions of a particular case are also presented.  相似文献   
163.
Complexes of the type [RuIII(L)Cl2(PPh3)2] and [RuII(L)2(PPh3)2] (HL=benzoylacetone or acetylacetone) have been synthesized by the reaction of [RuCl2(PPh3)3] with HL under various experimental conditions. The [RuIII(L)Cl2(PPh3)2] complexes are one-electron paramagnetic species and, in solution, they show intense LMCT transitions in the visible region together with weak ligand-field transitions at lower energies. The [RuII(L)2(PPh3)2] complexes are diamagnetic and their solutions show sharp 1H n.m.r. signals and also show intense MLCT transitions in the visible region. In MeCN solution, the [RuIII(L)Cl2(PPh3)2] complexes show a reversible RuIII-RuII reduction near –0.3V and an irreversible RuIII- RuIV oxidation near 1.2 V versus s.c.e. A reversible RuII-RuIII oxidation is displayed by the [RuII(L)2(PPh3)2] complexes in MeCN solution near 0.3 V versus s.c.e. followed by another reversible RuIII-RuIV oxidation near 1.1 V versus s.c.e. The [RuII(L)2(PPh3)2] complexes have been oxidized to the corresponding [RuIII(L)2(PPh3)2]+ analogues and isolated as ClO4– salts in the solid state. The oxidized complexes are one-electron paramagnetic. They are 1:1 electrolytes in solution and show intense LMCT transitions in the visible region along with weak ligand-field transitions at lower energies.  相似文献   
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Results of temperature dependence of EPR spectra of Mn2+ and Cu2+ ions doped calcium cadmium acetate hexahydrate (CaCd(CH3COO)4·6H2O) have been reported. The investigation has been carried out in the temperature range between room temperature (~ 300 K) and liquid nitrogen temperature. A I-order phase transition at 146 ± 0.5 K has been confirmed. In addition a new II-order phase transition at 128 ± 1 K has been detected for the first time. There is evidence of large amplitude hindered rotations of CH3 groups which become frozen at ~ 128 K. The incorporation of Cu2+ and Mn2+ probes at Ca2+ and Cd2+ sites respectively provide evidence that the phase transitions are caused by the molecular rearrangements of the common coordinating acetate groups between Ca2+ and Cd2+ sites. In contradiction to the previous reports of a change of symmetry from tetragonal to orthorhombic below 140 K, the symmetry of the host is concluded to remain tetragonal in all the three observed phases between room temperature and liquid nitrogen temperature.  相似文献   
167.
168.
Heats of solution of alkali metal, silver, ammonium and substituted ammonium perchlorates, lithium chloride and potassium thiocyanate have been measured in the concentration range 1.26–112.8×10?3 mol l?1 in N,N-dimethylacetamide (DMA) at 26.9°C. Slopes of the linear plots of heat of solution vs. square root of concentration are two to three times higher than the Debye-Hückel limiting slope indicating thereby complete dissociation of the electrolytes. Standard heats of solution of the electrolytes in DMA are higher than those in formamide and N-methylformamide and are comparable to those in N,N-dimethylformamide. Buckingham's model has been used to determine the solvation enthalpies of various ions in this solvent. The results indicate that ion solvation enthalpies decrease with increase in size of the ions and that the anion solvation enthalpies are higher than cation solvation enthalpies which is consistent with the findings in various solvents.  相似文献   
169.
The Schiff base salicylideneamino-o-methylthiobenzene (I), CH3S?C6H4?N=CH?C6H4?OH (SMeNOH), has been synthesized and its complexes of the type CuX(SMeNO) whereX=Cl, Br, NO3, CNS, and ClO4, CuX′(SMeNOH) whereX′=SO4 and (BF4)2, NiX″ 2(SMeNOH) whereX″=Cl and Br, NiNO3(SMeNO) andM(SMeNO) 2 whereM=Cu, Ni and Co, have been prepared and characterised through infrared, magnetic moment and conductance measurements.  相似文献   
170.
A new inorganic ion exchanger, copper ferricyanide prepared by adding copper nitrate to a potassium ferricyanide solution at 80°C has been found to be stable in acids and salt solutions. It has been characterized by chemical analysis, thermogravimetry. X-ray and infrared spectroscopy. Distribution coefficients determined for various metal ions show that the exchanger has a high affinity for heavy univalent cations. The variation of Kd for a number of metal ions as a function of nitric acid concentration and ammonium nitrate has been investigated to elucidate the probable exchange mechanism and to work out conditions for elution. Binary separations of Cs from a number of other metal ions were achieved on the column of exchanger. The exchanger is useful for the separation of137Cs.  相似文献   
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