X-ray determination of the mean Debye-Waller factors,amplitudes of vibration and Debye temperatures of six crystals with CsCl structure

From the integrated intensities of Bragg reflections measured at room temperature with an x-ray powder diffractometer, the mean Debye-Waller factorB, the average r.m.s. amplitude of vibration (ū ²)^1/2 and the Debye temperatureθ, have been determined for six crystals with the CsCl structure. The energy of formation of a Schottky pair in these crystals has been estimated from an empirical relation between the x-ray Debye temperature and the energy of formation.     

X-ray determination of the mean Debye-Waller factors,amplitudes of vibrations and the Debye temperatures of CdO,PbS and MnS

Integrated intensities of Bragg reflections of CdO, PbS and MnS have been measured at room temperature using an x-ray powder diffractometer. From a least square treatment of the intensity data the mean Debye-Waller factor, the mean amplitude of vibration and the Debye temperature have been evaluated. Calculations were made using scattering factors pertaining to neutral atoms as well as doubly ionised ions. The results from the two sets of calculations agreed within limits of errors.     

On the dispersion of a prism used as a beam expander in a nitrogen laser pumped dye laser

It is shown that the dispersion of a prism beam expander used at very high angles of incidence has a large effect on the laser linewidth.     

Electron transfer reaction in the radiation chemistry of some biologically important disulphlde compounds

It is found that some biologically important organic disulphides behave in an unique way under gamma irradiation when they are added in small amounts to the well-known Fricke dosimetry solution. On irradiation, it is noted that addition of these organic solutes reduces the G(Fe⁺² → Fe⁺³) yield instead of the usual increase found in the case of most other organic compounds. It is argued that these compounds behave as sacrificial radiation protective agents. The observation has been explained on the basis of an electron transfer reaction between the disulphides and OH radical. The resulting radical cations of these compounds then dissociate into non-chain propagating species. An attempt has been made to correlate the protective ability of such compounds towards (Fe⁺² → Fe⁺³) system with their biological radiation Drotective abilities. The electron transfer mechanism also seems to operate into their radiation protective action towards biological systems.     

Synthesis of 5-substituted 1H-tetrazoles catalyzed by ceric ammonium nitrate supported HY-zeolite

In this Letter we wish to report a simple and efficient synthetic protocol for the synthesis of 5-substituted 1H-tetrazole derivatives through the [2+3] cycloaddition of nitriles with sodium azide using ceric ammonium nitrate supported HY-zeolite as a novel catalyst. Excellent yields of the corresponding tetrazoles were obtained through this cost-effective protocol under aerobic conditions with shorter reaction time under mild reaction conditions.     

VCl3‐Catalyzed Selective Oxidation of Sulfides to Sulfoxides Using H2O2 as Oxidant

VCl₃ is an effective catalyst for the catalytic oxidation of sulfides to afford sulfoxides in good yields using hydrogen peroxide as an oxidant.     

Synthesis and structure of the N-alkyl-2,6-dimethyl-4-oxopyridine-3-carboxylic acids

A range of N-alkyl-2,6-dimethyl-4-oxopyridine-3-carboxylic acids XV have been prepared via reactions of primary alkyl amines with differing 2,6-dimethyl-4-oxopyran-3-carboxylate esters IX . The quantity of desired product formed and the character of by-products formed are determined by the natures of the amine and ester IX respectively. X-ray crystallography data for the N-ethyl analogue of XV indicates very strong intramolecular hydrogen bonding to be present, with the heterocyclic ring exhibiting considerable aromaticity.