Mössbauer Spectroscopic Studies of the Effects of the 6Li(n, α)T Reaction in Lithium Tris(oxalato)ferrate(III)

Abstract
The chemical effects of the 6Li(n,α)T reaction in lithium tris(oxalato)ferrate(III) crystals were examined by means of Mössbauer spectroscopy. Neutron irradiations were carried out under different conditions in order to clarify the mechanism of the effects. The reduced iron(II) species observed in the spectrum of Li3[Fe(C2O4)3]·4.5H2O, subjected to neutron irradiation (8.6×1015 n cm−2) at 200 K, shows a larger Q.S. value than that in the spectrum of the sample neutron-irradiated at an ambient temperature (300–320 K) in a reactor, suggesting that the initially produced iron(II) species changes into another iron(II) species during the irradiation at the ambient temperature. A species identical with the initial iron(II) species produced in the neutron irradiation was found to be prepared by the pyrolysis of Li3[Fe(C2O4)3]·4.5H2O. A comparison of neutron-irradiated hydrous and anhydrous Li3[Fe(C2O4)3] suggests that the change in the iron(II) species is influenced by the existence of crystal water.