Solid Solutions of Ice and NH4F and Their Dielectric Properties

摘要

The solidus curve for the system H2Osngbnd;NH4F was partly determined by means of chemical analyses, heating curves and a dilatometric method, and partly estimated from the liquidus curve using a thermodynamic relation. The solubility limit thus estimated is roughly 10. The dielectric relaxation times, tgr;, of solid solutions of ice containing 0.002 to 10 weight percent NH4F were measured at temperatures of about mdash;60deg; to mdash;10deg;C. The activation energies for dipole rotation were only about 4 kcal/mole as compared with 13 kcal/mole in pure ice. At low concentrations the frequency factor increases with increasing concentration of NH4F. At high concentrations of NH4F this trend is reversed.