J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, USA.
Department für Chemie, Ludwig-Maximilians-Universität München, Butenandt-Strasse 11, D-81377, München, Germany.
Sci Rep. 2017 Jun 30;7(1):4441. doi: 10.1038/s41598-017-04638-0.
Much of our intuition about strong-field processes is built upon studies of diatomic molecules, which typically have electronic states that are relatively well separated in energy. In polyatomic molecules, however, the electronic states are closer together, leading to more complex interactions. A combined experimental and theoretical investigation of strong-field ionization followed by hydrogen elimination in the hydrocarbon series CD, CD and CD reveals that the photofragment angular distributions can only be understood when the field-dressed orbitals rather than the field-free orbitals are considered. Our measured angular distributions and intensity dependence show that these field-dressed orbitals can have strong Rydberg character for certain orientations of the molecule relative to the laser polarization and that they may contribute significantly to the hydrogen elimination dissociative ionization yield. These findings suggest that Rydberg contributions to field-dressed orbitals should be routinely considered when studying polyatomic molecules in intense laser fields.
我们对强场过程的直觉很大程度上建立在双原子分子的研究基础上，这些分子通常具有相对较好分离的电子态。然而，在多原子分子中，电子态更接近，导致更复杂的相互作用。对烃系列 CD、CD 和 CD 中的强场电离随后的氢消除的实验和理论研究表明，只有当考虑场修饰轨道而不是自由场轨道时，才能理解光碎片的角分布。我们测量的角分布和强度依赖性表明，对于分子相对于激光偏振的某些取向，这些场修饰轨道可能具有很强的里德伯特征，并且它们可能对氢消除离解电离产率有显著贡献。这些发现表明，在强激光场中研究多原子分子时，应常规考虑里德伯对场修饰轨道的贡献。
