A cascade through spin states in the ultrafast haem relaxation of met-myoglobin.
A cascade through spin states in the ultrafast haem relaxation of met-myoglobin.
复制标题
正铁肌红蛋白超快血红素弛豫中自旋态的级联。
DOI：
10.1063/1.4861467
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
M. Chergui
中科院分区：
文献类型：
--
作者：
C. Consani;G. Auböck;O. Bräm;F. van Mourik;M. Chergui
我们报告了一项对水溶液中met-肌红蛋白早期弛豫过程的研究，该研究结合了超快宽带荧光检测和瞬态吸收以及不同泵浦能量下的宽紫外-可见连续谱探针。瞬时物种光谱的重建揭示了在没有光解作用的情况下血红素光循环的细节。除了确定血红素超快弛豫中的分支之外，我们还显示了中间体电子特征的明确证据，这与血红素早期弛豫仅归因于冷却的普遍接受的观点相反。衰变回到基态的部分过程是通过铁自旋态级联进行的，这似乎是血红素系统的一般特征。
We report on a study of the early relaxation processes of met-Myoglobin in aqueous solution, using a combination of ultrafast broadband fluorescence detection and transient absorption with a broad UV-visible continuum probe at different pump energies. Reconstruction of the spectra of the transient species unravels the details of the haem photocycle in the absence of photolysis. Besides identifying a branching in the ultrafast relaxation of the haem, we show clear evidence for an electronic character of the intermediates, contrary to the commonly accepted idea that the early time relaxation of the haem is only due to cooling. The decay back to the ground state proceeds partially as a cascade through iron spin states, which seems to be a general characteristic of haem systems.