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Abstract A new nonheme iron(II) complex, FeII(Me3TACN)((OSiPh2)2O) (1), is reported. Reaction of1with NO(g)gives a stable mononitrosyl complex Fe(NO)(Me3TACN)((OSiPh2)2O) (2), which was characterized by Mössbauer (δ=0.52 mm s−1, |ΔEQ|=0.80 mm s−1), EPR (S=3/2), resonance Raman (RR) and Fe K‐edge X‐ray absorption spectroscopies. The data show that2is an {FeNO}7complex with anS=3/2 spin ground state. The RR spectrum (λexc=458 nm) of2combined with isotopic labeling (15N,18O) reveals ν(N‐O)=1680 cm−1, which is highly activated, and is a nearly identical match to that seen for the reactive mononitrosyl intermediate in the nonheme iron enzyme FDPnor (ν(NO)=1681 cm−1). Complex2reacts rapidly with H2O in THF to produce the N‐N coupled product N2O, providing the first example of a mononuclear nonheme iron complex that is capable of converting NO to N2O in the absence of an exogenous reductant.
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Implications of Electron Detachment in Associative Collisions of Atomic Oxygen Anion with Molecular Nitrogen for Modeling of Transient Luminous Events
Abstract Electron detachment from O−is important for understanding of lightning‐induced upper atmospheric discharges. Contrary to previous studies, Rayment and Moruzzi (1978) (RM78) argue that the associative detachment reaction of O−with N2proceeds with N2in its ground state. Here, we analyze the experimental setup in RM78 and demonstrate that vibrationally excited N2may have in fact contaminated the results, the theoretical approach in RM78 requires corrections, and the rate calculations provided in RM78 are inconsistent. As the vibrational temperature of N2remains relatively low in the initial stages of gas discharges in air, i.e., streamer formation, we conclude that if in fact vibrationally excited N2is required for the O− + N2→ N2O + e reaction to proceed, the process will happen only in later stages of the discharge, e.g., during streamer to leader transition. Controlled experiments are required to reconcile the literature on the reaction of O−with ground state N2.
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- Award ID(s):
- 2010088
- PAR ID:
- 10447300
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 48
- Issue:
- 4
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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