Torres-Alacan Joel, Lindner Jörg, Vöhringer Peter
Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstrase 12, 53115 Bonn (Germany).
Chemphyschem. 2015 Aug 3;16(11):2289-93. doi: 10.1002/cphc.201500370. Epub 2015 Jun 11.
Species containing iron at an oxidation state higher than +III are often termed "high-valent iron" and are considered to be key catalytic intermediates in biochemistry. Here, we report the direct time-domain probing of the photochemical formation of an octahedral nitrido iron(V) complex through dinitrogen cleavage from an diazido iron(III) precursor by using femtosecond mid-infrared (MIR) spectroscopy. From the time-resolved vibrational spectra, a mechanism is suggested for the photooxidation of the metal within 10 ps. This mechanism involves an initial ultrafast non-adiabatic transition, followed by a quasithermal N-N bond rupture on the ground-state surface.
氧化态高于+III的含铁物种通常被称为“高价铁”，并被认为是生物化学中的关键催化中间体。在此，我们报告了通过使用飞秒中红外（MIR）光谱，对八面体氮合铁（V）配合物从二叠氮基铁（III）前体通过二氮裂解进行光化学形成的直接时域探测。从时间分辨振动光谱中，提出了一种在10皮秒内金属光氧化的机制。该机制涉及初始超快非绝热跃迁，随后是基态表面上的准热N-N键断裂。
