The study of the mechanism of the formation of the condensed Gd2Cl3 cluster

The cocrystallization of microquantities of Np, Pu, Am and Cm with Gd2Cl3 was studied in the system GdCl3-Gd0. It was shown, that Am like Eu, practically, does not cocrystallize with Gd2Cl3. This is attributed to the fact that the electronic configuration of these elements in the oxidation state 2+ does not involve d-orbitals. The trapping of Np, Pu and Cm by the Gd2Cl3 phase depends on the degree of their reduction to the oxidation state 2+ and it decreases with an increase in E0Me3+/Me2+. A logarithmic equation, describing the distribution of these elements between the Gd2Cl3 cluster and molten GdCl3 was obtained. Based on the mechanism of cocrystallization of microcomponents with Gd2Cl3 a conclusion is made concerning the mechanism of formation of a cluster typified by Gd2Cl3. This mechanism suggests participation of the trivalent form of the element in the structure of the Gd2Cl3 lattice. (orig.)