Liu ChunMei, Manz Jörn, Tremblay Jean Christophe
College of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023, China.
Institut für Chemie und Biochemie, Freie Universität Berlin, 14195 Berlin, Germany.
J Phys Chem Lett. 2021 May 13;12(18):4421-4427. doi: 10.1021/acs.jpclett.1c00645. Epub 2021 May 5.
Electron symmetry determines many important properties of molecules, from selection rules for photoelectron spectroscopy to symmetry selection rules for chemical reactions. The original electron symmetry is broken if a laser pulse changes the initial state, typically the ground state , to a superposition of and an excited state with different irreducible representations (IRREPs). Quantum dynamics simulations for two examples, the oriented benzene and LiCN molecules, show that the original electron symmetry can be restored by means of a reoptimized π-laser pulse which transfers the component in the excited state to another state ', or to several others with the same IRREP as the ground state. This method lends itself to much easier experimental applications than all previous ones because it allows the healing of electron symmetry immediately, without any attosecond constraint on the timing of the second pulse.
电子对称性决定了分子的许多重要性质，从光电子能谱的选择规则到化学反应的对称选择规则。如果激光脉冲将初始态（通常是基态）改变为具有不同不可约表示（IRREPs）的基态和激发态的叠加态，那么原始的电子对称性就会被打破。对取向苯和LiCN分子这两个例子进行的量子动力学模拟表明，通过重新优化的π激光脉冲可以恢复原始的电子对称性，该脉冲将激发态中的成分转移到另一个态'，或者转移到与基态具有相同IRREP的其他几个态。这种方法比之前所有方法都更易于实验应用，因为它可以立即修复电子对称性，而对第二个脉冲的时间没有任何阿秒级别的限制。
