Spin conversion in mixed ammonium–potassium halide systems

Abstract

The spin-temperature relaxation in (NH₄)_cK_{1 –c}X (X = I, Br) is studied by inelastic neutron scattering spectroscopy. It is demonstrated for the first time that these salts, prepared from aqueous solutions, can maintain a spin–temperature inversion. Both the mixed halides relax at similar rates and these rates increase with temperature, following an approximately T³ variation. Relaxation has been found to continue even at the lowest temperature.