INVESTIGATION OF IRON(II) ASCORBATE SOLUT ION FIXED IN A RIGID ORGANIC MICROEMULSION BY MOSSBAUER-SPECTROSCOPY

In contrast with a methanolic solution of SnCl4 trapped in the pores o f a rigid organic microemulsion, iron(II) species in the bulk of ascor bic acid-containing methanolic solution in a similar microemulsion are not fixed strongly enough to achieve recoilless gamma-ray resonance a bsorption at room temperature. The Mossbauer effect appears only below 260 K, at temperatures higher than the freezing point of methanol, in dicating the fixing of the solution of Mossbauer-active solutes in the carrier. Comparison of the QS values of the iron(II) species in the m icroemulsion and those in solution quenched by quick-freezing, both at 80 K, suggests that both chloride and ascorbate ligands are coordinat ed to iron(II) in the submicroscopic (nano-size) droplets, in contrast with the quenched solution, which contains iron(II)-ascorbate complex cations in equilibrium with chloride ions. This difference may be exp lained by the decreased solvation of the species in the submicroscopic droplets, due to the decreased concentration of bulk solvent in the m icroemulsion.