On the formation of anions: frequency-, angle-, and time-resolved photoelectron imaging of the menadione radical anion.
On the formation of anions: frequency-, angle-, and time-resolved photoelectron imaging of the menadione radical anion.
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DOI：
10.1039/c4sc03491k
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发表时间：
2015-02-01
期刊：
影响因子：
8.4
通讯作者：
Verlet JRR
中科院分区：
文献类型：
--
作者：
Bull JN;West CW;Verlet JRR
用频率分辨、角度分辨和时间分辨的光电子成像方法对气相维生素K3阴离子进行了研究，结果表明，在亚皮秒的时间尺度上，该阴离子的准束缚共振可以作为有效的门态，产生亚稳态的基态阴离子。用频率分辨、角度分辨和时间分辨的光电子成像方法对气相维生素K3自由基阴离子进行了研究，结果表明，在亚皮秒的时间尺度上，负离子的准束缚共振可以作为有效的门态，产生亚稳态的基态阴离子。在从头计算的辅助下，实验上观察到了几种阴离子共振现象，并在阈值以上的前3 eV处观察到了基态阴离子恢复。时间分辨测量揭示了电子基态阴离子的形成机制，它首先涉及到非常快的内部转换过程到束缚电子态的级联，而束缚电子态又通过较慢的内部转换到基态而衰变。与通过内部转换的电子弛豫相比，从布居共振中自动脱离的过程是低效的。所获得的机理理解提供了对生物和天文化学系统中自由基阴离子形成的洞察。
Frequency-, angle-, and time-resolved photoelectron imaging of gas-phase menadione (vitamin K3) radical anions is used to show that quasi-bound resonances of the anion can act as efficient doorway states to produce metastable ground electronic state anions on a sub-picosecond timescale. Frequency-, angle-, and time-resolved photoelectron imaging of gas-phase menadione (vitamin K3) radical anions was used to show that quasi-bound resonances of the anion can act as efficient doorway states to produce metastable ground electronic state anions on a sub-picosecond timescale. Several anion resonances have been experimentally observed and identified with the assistance of ab initio calculations, and ground state anion recovery was observed across the first 3 eV above threshold. Time-resolved measurements revealed the mechanism of electronic ground state anion formation, which first involves a cascade of very fast internal conversion processes to a bound electronic state that, in turn, decays by slower internal conversion to the ground state. Autodetachment processes from populated resonances are inefficient compared with electronic relaxation through internal conversion. The mechanistic understanding gained provides insight into the formation of radical anions in biological and astrochemical systems.
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影响因子：
2
作者：
Asfandiarov, N. L.;Pshenichnyuk, S. A.;Modelli, A.
通讯作者：
Modelli, A.
影响因子：
3.3
作者：
Horke, Daniel A.;Verlet, Jan R. R.
通讯作者：
Verlet, Jan R. R.
影响因子：
8.7
作者：
ALLAMANDOLA, LJ;TIELENS, AGGM;BARKER, JR
通讯作者：
BARKER, JR
影响因子：
15
作者：
COMITA, PB;BRAUMAN, JI
通讯作者：
BRAUMAN, JI
影响因子：
2.9
作者：
Concina, Bruno;Lepine, Franck;Bordas, Christian
通讯作者：
Bordas, Christian