The effect of dipole-dipole interaction on zero-THz frequency polarisation

The effect of intramolecular dipole-dipole interaction on polarisation at frequencies from 0 – 10¹² Hz in dipolar media is investigated using a numerical solution of the Sturm-Liouville eigenvalue problem to which the governing Smoluchowski equation reduces. The results of Budó for the long-wavelength limit are extended to all frequencies up to the far infrared, where the predominant inertial effects are treated using a preliminary first-order correction. The numerical method of Pryce may be used to investigate much more realistic interaction potentials than the simple harmonic and cosine form considered by Budó. These simple forms are, however, sufficient to indicate that the integrated absorption intensity per molecule in the far infrared is very sensitive to dipole-dipole interaction and relative hydrodynamic drag on both interacting groups. Applications of the theory to the disordered solid and nematic phases are considered.     

Choice of preferred stationary phases for gas chromatography. Part II

Summary The regularities of changes of the polarity factors with the composition of mixed stationary phases are discussed. Values of the polarity factors of active solids, partitioning liquids and also colloidal stationary phases are compared. Part I: ref. [1].     

Etude par RPE de l'Ion NO2−2 dans une apatite nitrée

A calcium phosphate apatite which contains some different nitrogen oxides is studied by the ESR technique. NO^2?₂ ions are evidenced and characterized. They stay in the apatite channels with their OO direction along the channel axis. ESR experiments at different temperatures show that these ions rotate around this axis when the temperature becomes higher than that of liquid nitrogen.