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Cyclopentadienyl coordination induces unexpected ionic Am-N bonding in an americium bipyridyl complex.

ABSTRACT: Variations in bonding between trivalent lanthanides and actinides is critical for reprocessing spent nuclear fuel. The ability to tune bonding and the coordination environment in these trivalent systems is a key factor in identifying a solution for separating lanthanides and actinides. Coordination of 4,4'-bipyridine (4,4'-bpy) and trimethylsilylcyclopentadienide (Cp') to americium introduces unexpectedly ionic Am-N bonding character and unique spectroscopic properties. Here we report the structural characterization of (Cp'₃Am)₂(μ - 4,4'-bpy) and its lanthanide analogue, (Cp'₃Nd)₂(μ - 4,4'-bpy), by single-crystal X-ray diffraction. Spectroscopic techniques in both solid and solution phase are performed in conjunction with theoretical calculations to probe the effects the unique coordination environment has on the electronic structure.

SUBMITTER: Long BN

PROVIDER: S-EPMC8752859 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Cyclopentadienyl coordination induces unexpected ionic Am-N bonding in an americium bipyridyl complex.

Long Brian N BN Beltrán-Leiva María J MJ Celis-Barros Cristian C Sperling Joseph M JM Poe Todd N TN Baumbach Ryan E RE Windorff Cory J CJ Albrecht-Schönzart Thomas E TE

Nature communications 20220111 1

Variations in bonding between trivalent lanthanides and actinides is critical for reprocessing spent nuclear fuel. The ability to tune bonding and the coordination environment in these trivalent systems is a key factor in identifying a solution for separating lanthanides and actinides. Coordination of 4,4'-bipyridine (4,4'-bpy) and trimethylsilylcyclopentadienide (Cp') to americium introduces unexpectedly ionic Am-N bonding character and unique spectroscopic properties. Here we report the struct ...[more]

PMID: 35017503

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