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Experimentally quantifying small-molecule bond activation using valence-to-core X-ray emission spectroscopy.

ABSTRACT: This work establishes the ability of valence-to-core X-ray emission spectroscopy (XES) to serve as a direct probe of N2 bond activation. A systematic series of iron-N2 complexes has been experimentally investigated and the energy of a valence-to-core XES peak was correlated with N-N bond length and stretching frequency. Computations demonstrate that, in a simple one-electron picture, this peak arises from the N2 2s2s ?* orbital, which becomes less antibonding as the N-N bond is weakened and broken. Changes as small as 0.02 Å in the N-N bond length may be distinguished using this approach. The results thus establish valence-to-core XES as an effective probe of small molecule activation, which should have broad applicability in transition-metal mediated catalysis.

SUBMITTER: Pollock CJ

PROVIDER: S-EPMC3811143 | biostudies-other | 2013 Aug

REPOSITORIES: biostudies-other

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Experimentally quantifying small-molecule bond activation using valence-to-core X-ray emission spectroscopy.

Pollock Christopher J CJ Grubel Katarzyna K Holland Patrick L PL DeBeer Serena S

Journal of the American Chemical Society 20130730 32

This work establishes the ability of valence-to-core X-ray emission spectroscopy (XES) to serve as a direct probe of N2 bond activation. A systematic series of iron-N2 complexes has been experimentally investigated and the energy of a valence-to-core XES peak was correlated with N-N bond length and stretching frequency. Computations demonstrate that, in a simple one-electron picture, this peak arises from the N2 2s2s σ* orbital, which becomes less antibonding as the N-N bond is weakened and brok ...[more]

PMID: 23862983

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