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Download fileComputational Investigation of the Bonding in [(η5–Cp′)3(η1–Cp′)M]1– (M = Pu, U, Ce)
dataset
posted on 26.05.2021, 09:29 authored by Cristian Celis-Barros, Thomas Albrecht-Schönzart, Cory J. WindorffDespite
the similar ionic radii for Ce3+, U3+, and Pu3+, [(η5–Cp′)3(η1–Cp′)Ce]1– (Cp′ = C5H4SiMe3, 1-Ce) displays
a significantly longer η1–Cp′
distance in the solid state compared to the U3+ and Pu3+ analogues. To better understand this observation, a theoretical
investigation was undertaken to examine the differences in bonding
between the actinides 1-Pu and 1-U and how
they compare with 1-Ce. The results show that although
the bonding is largely ionic and dominated by ligand (2p)–metal
(6d/5d) interactions, the polarization of 5f orbitals plays a significant
role for 1-Pu and 1-U compared to the 4f-orbitals
of 1-Ce. The lack of Ce(4f) interactions is compensated
for by increased participation of the Ce(5d) orbitals relative to
the actinide 6d orbitals, particularly for the σ-bound η1–Cp′ ligand. The use of multiple theoretical
approaches including topological, localization, and energy decomposition
approaches shows that 1-Pu and 1-U are very
similar in covalent character compared to 1-Ce, though
the composition and energy of the different interactions suggest that 1-U presents the strongest overall interactions.