The influence of radioactive decay on actinide magnetic susceptibility measurements obtained using the Evans method†
In order to explain the higher magnetic susceptibility of some aquo actinide ions than predicted by Hund's rules, the molar magnetic susceptibilities of two americium isotopes (241Am and 243Am) were measured using the Evans method. The results obtained show a growing change in the magnetic susceptibility with α and also a β− activity increase in solution. β− particle effects appear to be stronger than radicals formed by α particles on the experimental values. The temperature dependence of Am(III) magnetic susceptibility has been observed but from experiments carried out here, it appears to be difficult to prove whether this effect arises from radicals or β−. Finally, magnetic susceptibilities of americium recorded in different media (HClO4, HCl, and HNO3) have been compared to alpha and beta emissions' impact.