Gas-phase reactivity of actinide monocations with O(2) and CO(2) from thorium to californium

作者：Goujet M, Quemet A, Guillaumont D · 发表于：Physical chemistry chemical physics : PCCP · 年份：2026 · DOI：10.1039/d5cp04920b

The gas phase reactivity of actinide monocations (Th+, Pa+, U+, Np+, Pu+, Am+, Cm+ and Cf+) with O2 and CO2 was studied using inductively coupled plasma mass spectrometry (ICP-MS). Total reactions were observed for all actinides, except californium, for which only partial reactions occurred. Depending on the actinide, different reaction products are formed. AnO+ and AnO2+ products are formed sequentially for Th, Pa, U, Np and Pu, whereas only AnO+ is formed for Am, Cm and Cf. Among all investigated actinides, Cf+ is the least reactive. The results are compared to experimental and calculated bond dissociation energies of the AnO2+ and AnO+ products. The smallest bond dissociation energies are found for AmO2+, CmO2+ and CfO2+, suggesting that these species are the least stable, as expected given their lack of formation. Among the actinide monoxides, the AmO+ and CfO+ species exhibit the lowest bond dissociation energy, consistent with their weaker reactivity toward O2 and CO2 compared with the other actinides.