Ultrafast Dynamics of the Isolated Adenosine-5′-triphosphate Dianion Probed by Time-Resolved Photoelectron Imaging
Ultrafast Dynamics of the Isolated Adenosine-5′-triphosphate Dianion Probed by Time-Resolved Photoelectron Imaging
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DOI：
10.1021/acs.jpca.1c01646
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发表时间：
2021-04-22
影响因子：
2.9
通讯作者：
Verlet, Jan R. R.
中科院分区：
文献类型：
--
作者：
Castellani, Maria Elena;Avagliano, Davide;Verlet, Jan R. R.
用时间分辨光电子能谱研究了腺苷-5 '-三磷酸双去质子二价阴离子[ATP-H-2]（2-）在4.66eV激发后的激发态动力学。时间分辨的光电子能谱表明，两个竞争过程发生的初始填充1 π π * 状态。第一种是通过隧穿排斥库仑势垒的快速电子发射，因为1 π π * 状态是共振。第二个是1 π π * 状态表面上的核运动，导致中间体不再隧穿，随后通过内部转换到基态电子态而衰变。的光谱特征的特征是类似于观察到的其他腺嘌呤衍生物，这表明该核碱基是相当不敏感的附近的负电荷定位在磷酸盐，当然除了额外的电子隧穿通道，这是开放的二价阴离子的外观。
The excited state dynamics of the doubly deprotonated dianion of adenosine-5'-triphosphate, [ATP-H-2](2-), has been spectroscopically explored by time-resolved photoelectron spectroscopy following excitation at 4.66 eV. Time-resolved photoelectron spectra show that two competing processes occur for the initially populated 1 pi pi* state. The first is rapid electron emission by tunneling through a repulsive Coulomb barrier as the 1 pi pi* state is a resonance. The second is nuclear motion on the 1 pi pi* state surface leading to an intermediate that no longer tunnels and subsequently decays by internal conversion to the ground electronic state. The spectral signatures of the features are similar to those observed for other adenine-derivatives, suggesting that this nucleobase is quite insensitive to the nearby negative charges localized on the phosphates, except of course for the appearance of the additional electron tunneling channel, which is open in the dianion.