Conductivity and Mössbauer Measurements in Doped Ice

Measurements have been made on the recoilless (NGR) absorption of Sn⁴⁺ ions in $\text{0.2M}$ SnCl₄ frozen aqueous solutions (FAS) as a function of time and temperature. These reproduce most of the effects, including the anomalous transient disappearance of the Mössbauer effect, seen by previous workers using Fe²⁺ and Fe³⁺ ions in FAS. The electrical conductivity of the SnCl₄ FAS was also measured, and found to “follow” the NGR results very closely, despite the great differences in the fundamental mechanisms of these two phenomenon. There is evidence for melting of part of the FAS above 200°K.