Femtosecond laser ionization of organic amines with very low ionization potentials: relatively small suppressed ionization features.
Femtosecond laser ionization of organic amines with very low ionization potentials: relatively small suppressed ionization features.
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飞秒激光电离具有非常低电离势的有机胺：相对较小的抑制电离特征。
DOI：
10.1021/jp0619989
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发表时间：
2006
期刊：
影响因子：
--
通讯作者：
N. Nakashima
中科院分区：
文献类型：
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作者：
T. Yatsuhashi;T. Obayashi;Michinori Tanaka;M. Murakami;N. Nakashima
我们研究了飞秒非共振电离有机胺的垂直电离势低至5.95 eV。通过比较实验和理论中的饱和强度I（sat），定量评价了相对于单活性电子近似模型的抑制电离。ADK理论被发现是有用的预测电离产率在I（sat）规模内的一个因素2，即使是非常低的电离势的分子。然而，抑制的程度小于苯。发现氮原子上的电子局域化对强激光场下的电离行为有影响。苯中的离域π电子不能精确地跟随激光场，而定域分子轨道中的π电子可以。此外，在胺中由于屏蔽效应而导致的隧穿势垒的生长可能相对小于在苯中的隧穿势垒。
We examined the femtosecond nonresonant ionization of organic amines with vertical ionization potentials as low as 5.95 eV. The quantitative evaluation of suppressed ionization relative to the single active electron approximation model was done by comparing the saturation intensity, I(sat), in experiments and theory. ADK theory was found to be useful in predicting the ionization yield in the I(sat) scale within a factor of 2, even for molecules with very low ionization potentials. The degree of suppression was, however, smaller than that of benzene. The localization of electrons on the nitrogen atom was found to affect the ionization behavior under the strong laser field. The delocalized pi electrons in benzene could not follow the laser field adiabatically, while those in localized molecular orbitals could. In addition, the growth of a tunneling barrier due to the screening effect in amines may be relatively smaller than that in benzene.