Mössbauer spectroscopic studies of frozen aqueous solutions of Fe3+ salts

摘要: Frozen aqueous solutions (FAS) of Fe3+ salts have been investigated by use Mossbauer spectroscopy in order to study the conditions for formation glasses. A general discussion spin–spin relaxation glasses is given, and we discuss how changes time can be attributed average separation between iron ions. In FeCl3–H2O system, it was found that homogeneous are easily formed when salt concentration larger than 3.5 moles FeCl3 per 100 H2O. more dilute samples, ice crystallizes during cooling, while solution increases. At low temperatures crystallization terminates remaining liquid solidifies into a glass. During exposure at 200 K, samples change irreversibly. This discussed terms metastable phase diagram. The properties frozen with other glass forming agents such as NO3−, ClO4−, glycerol also discussed. some systems ...