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High-Frequency Fe-H Vibrations in a Bridging Hydride Complex Characterized by NRVS and DFT.

ABSTRACT: High-spin iron species with bridging hydrides have been detected in species trapped during nitrogenase catalysis, but there are few general methods of evaluating Fe-H bonds in high-spin multinuclear iron systems. An 57 Fe nuclear resonance vibrational spectroscopy (NRVS) study on an Fe(?-H)2 Fe model complex reveals Fe-H stretching vibrations for bridging hydrides at frequencies greater than 1200?cm-1 . These isotope-sensitive vibrational bands are not evident in infrared (IR) spectra, showing the power of NRVS for identifying hydrides in this high-spin iron system. Complementary density functional theory (DFT) calculations elucidate the normal modes of the rhomboidal iron hydride core.

SUBMITTER: Pelmenschikov V

PROVIDER: S-EPMC6098820 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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High-Frequency Fe-H Vibrations in a Bridging Hydride Complex Characterized by NRVS and DFT.

Pelmenschikov Vladimir V Gee Leland B LB Wang Hongxin H MacLeod K Cory KC McWilliams Sean F SF Skubi Kazimer L KL Cramer Stephen P SP Holland Patrick L PL

Angewandte Chemie (International ed. in English) 20180625 30

High-spin iron species with bridging hydrides have been detected in species trapped during nitrogenase catalysis, but there are few general methods of evaluating Fe-H bonds in high-spin multinuclear iron systems. An 57 Fe nuclear resonance vibrational spectroscopy (NRVS) study on an Fe(μ-H)2 Fe model complex reveals Fe-H stretching vibrations for bridging hydrides at frequencies greater than 1200 cm-1 . These isotope-sensitive vibrational bands are not evident in ...[more]

PMID: 29847703

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