Uranyl-alizarin red-s complex.a spectrophotometric study

From spectrochemical studies on the blue complex resulting from uranyl and alizarin-S, it has been shown that a compound in the stoichiometric ratio 1:1 of uranyl and reagent is formed. The compound is stable at pH 8.2. The peaks of absorption of the reagent at 520 mu; and of the uranyl compound at 570 mμ have been accounted for, applying kuhn's relationship.     

Mean amplitudes of vibration and coriolis coupling constants of some XY3Z type silicon compounds

A theoretical treatment of the generalised mean-square amplitudes of vibration of some silicon compounds of XY₃Z type molecules is presented. The numerical values evaluated for the parallel and perpendicular mean-square amplitudes for all the bonded and non-bonded atom pairs are tabulated. The L matrix elements and Coriolis coefficients have also been evaluated for these molecules.     

Band of t-archimedean semigroups

A semigroup S is called t-archimedean if for all a,b∈S, there exists a positive integer i such that bⁱ∈aS∩Sa. The purpose of this paper is to characterize semigroups which are bands of t-archimedean semigroups. We then apply this result to exponential semigroups. National Science Foundation Fellow     

Intensity studies in Raman effect

The intensities of Raman lines due to CH, CH₂ and CH₃ groups in the case of some n-paraffin hydrocarbons have been obtained relative to the peak intensity of the 458 cm^?1 line of CCl₄ and compared. The integrated intensity as well as the standard intensity of the C=O frequency in some unconjugated and conjugated ketones, aldehydes and esters have been obtained and the influence of conjugation has been discussed. The intensity of the C=C frequency has also been obtained in the conjugated compounds and compared with the results obtained for the unconjugated compounds.     

The nuclear magnetic resonance spectra of four spin systems

The ring proton resonance spectra ofα, β andγ picolines have been studied at 40 Mc./sec. The spectra which belong to the classes ABCX, ABXY and A₂X₂ respectively have been completely analyzed to determine all the involved parameters.     

Anharmonicity correction and potential constants: BH 4 − isotopic ions

Normal coordinate analysis for XY₄ type molecules of T symmetry has been carried out by the Wilson F — G matrix method. Following Dennison and making use of the spectral data the anharmonicity factors for B'H ₄ ^– , B'D ₄ ^– , B¹⁰H ₄ ^– and B¹⁰D ₄ ^– have been calculated and potential constants have been evaluated for borohydride isotopic ions.     

Raman spectra of alcohols: Intensity measurements

The peak, integrated and standard intensities of some prominent Raman lines in twelve alcohols are estimated. The standard intensities of the lines due to some characteristic bonds in various alcohols are compared and large variations observed.     

EPR spectrum of gadolinium in hydrated praseodymium nitrate

The paramagnetic resonance spectrum of Gd³⁺ in Pr(NO₃)₃·6H₂O single crystals, is studied at room temperature. A seven line spectrum for H//Z as well as for H//X corresponding to ΔM=±1 transitions is observed along with a number of low field transitions (ΔM?2). The spin-Hamiltonian analyses is presented.     

Steady state and transient fluorescence studies of CaF2: Dy single crystals

The steady state and transient fluorescence spectra of CaF₂: Dy³⁺ have been studied using Ar⁺ and N₂ lasers in the temperature range 77–673 K and in the wavelength region 4500–9000 Å. The spectra show the presence of two types of centers (type A and type B) with decay times of 1.3 and 3.5 ms. The observed spectrum is mostly due to type A centers. Three new groups of fluorescence ⁴F_9/2−⁶H_11/2, ⁴F_9/2−(⁶H_9/2, ⁶F_11/2) and ⁴F_9/2−(⁶H_7/2, ⁶F_9/2) have been observed for type A centers, and a tentative assignment of the positions of the Stark levels of ⁶H_11/2, (⁶H_9/2, ⁶F_11/2) and (⁶H_7/2, ⁶F_9/2) has been made. The change in the intensity of the transitions with temperature and excitation wavelength are discussed.