دانلود مقاله On the Origin of Covalent Bonding in Heavy Actinides

دسته بندی : مقاله های انگلیسی

فایل : pdf

تعداد صفحات : 10

زبان مقاله : انگلیسی

مقدمه :Recent reports have suggested the late actinides participate in more covalent interactions than the earlier actinides,
yet the origin of this shift in chemistry is not understood. This report considers the chemistry of actinide dipicolinate complexes to
identify why covalent interactions become more prominent for heavy actinides. A modest increase in measured actinide:
dipicolinate stability constants is coincident with a significant increase in An 5f energy degeneracy with the dipicolinate molecular
orbitals for Bk and Cf relative to Am and Cm. While the interactions in the actinide-dipicolinate complex are largely ionic,
the decrease in 5f orbital energy across the series manifests in orbital-mixing and, hence, covalency driven by energy degeneracy.
This observation suggests the origin of covalency in heavy actinide interactions stems from the degeneracy of 5f-orbitals with ligand
molecular orbitals rather than spatial orbital overlap. These findings suggest that the limiting radial extension of the 5f orbitals
later in the actinide series could make the heavy actinides ideal elements to probe and tune effects of energy degeneracy driven
covalency

دانلود این مقاله علمی از انتها صفحه امکانپذیر است