An actinide is an element in the series from actinium, atomic number 89, through lawrencium, atomic number 103. The series is associated with occupation of 5f-derived electronic states, although individual ground-state configurations vary.
Variable oxidation states and ionic sizes affect coordination and separation chemistry. Radioactive isotopes add a distinct nuclear aspect to applications involving nuclear fuel and waste materials.
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Periodic Table by Royal Society of Chemistry. Actinium through lawrencium, atomic numbers89–103; element properties
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