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Valence-to-Core X-ray Emission Spectroscopy as a Probe of O-O Bond Activation in Cu2 O2 Complexes.

ABSTRACT: Valence-to-Core (VtC) X-ray emission spectroscopy (XES) was used to directly detect the presence of an O-O bond in a complex comprising the [CuII 2 (?-?2 :?2 -O2 )]2+ core relative to its isomer with a cleaved O-O bond having a [CuIII 2 (?-O)2 ]2+ unit. The experimental studies are complemented by DFT calculations, which show that the unique VtC XES feature of the [CuII 2 (?-?2 :?2 -O2 )]2+ core corresponds to the copper stabilized in-plane 2p ? peroxo molecular orbital. These calculations illustrate the sensitivity of VtC XES for probing the extent of O-O bond activation in ?-?2 :?2 -O2 species and highlight the potential of this method for time-resolved studies of reaction mechanisms.

SUBMITTER: Cutsail GE

PROVIDER: S-EPMC6615971 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Valence-to-Core X-ray Emission Spectroscopy as a Probe of O-O Bond Activation in Cu2 O2 Complexes.

Cutsail George E GE Gagnon Nicole L NL Spaeth Andrew D AD Tolman William B WB DeBeer Serena S

Angewandte Chemie (International ed. in English) 20190522 27

Valence-to-Core (VtC) X-ray emission spectroscopy (XES) was used to directly detect the presence of an O-O bond in a complex comprising the [CuII2 (μ-η2 :η2 -O2 )]2+ core relative to its isomer with a cleaved O-O bond having a [CuIII2 (μ-O)2 ]2+ unit. The experimental studies are complemented by DFT calculations, which show that the unique VtC XES feature of the [CuII2</s ...[more]

PMID: 30994976

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