Iron(II) Sulphate (Fricke Solution) Oxidation Yields for 8·9 and 13·6keV X-rays from Synchrotron Radiation

Abstract

The oxidation yields (G) for 8·86 and 13·55 keV X-rays produced by synchrotron radiation were measured using an iron(II) sulphate (Fricke) solution. Monoenergetic X-rays were produced using a silicon crystal monochromator. The X-rays were absorbed in 0·4 m sulphuric acid-iron(II) sulphate solution and Fe^III ion yields were measured and corrected for escape fractions resulting from scattering using Monte Carlo calculations. Doses in the solution were determined using a thin window, parallel plate chamber calibrated against a primary standard free-air chamber at the Electrotechnical Laboratory (Osaka, Japan). Yields (G) of 1·50 ± 0·06 and 1·43 ± 0·06 μmol J⁻¹ were obtained for 8·86 and 13·55 keV X-rays respectively.