Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA.
Phys Rev Lett. 2012 Aug 10;109(6):063202. doi: 10.1103/PhysRevLett.109.063202.
Dissociative photodetachment of HOCO(-) is investigated with both five- and six-dimensional quantum models on an ab initio based accurate HOCO potential energy surface. Three experimentally observed channels, namely, HOCO, H+CO(2), and HO+CO, are identified in our theoretical simulations. Since the energy spectrum of the initial HOCO species prepared by photodetachment is mostly lower than both the HO+CO asymptote and dissociation barrier to H+CO(2), the production of H+CO(2) is almost exclusively via tunneling. However, the lowest-lying HOCO resonances are extremely long lived (~μs), which might elude experimental measurements through its decay products H+CO(2). Our results are in good agreement with almost all experimental data reported by the Continetti group using a new cryogenically cooled photoelectron-photofragment coincidence apparatus.
HOCO(-) 的离解光解离用基于从头算的精确 HOCO 势能面的五维和六维量子模型进行了研究。在我们的理论模拟中，确定了三个实验上观察到的通道，即 HOCO、H+CO(2)和 HO+CO。由于光解离制备的初始 HOCO 物种的能谱主要低于 HO+CO 渐近线和 H+CO(2 的离解势垒，因此 H+CO(2 的产生几乎完全是通过隧穿。然而，最低的 HOCO 共振态寿命极长（~μs），这可能会通过其衰变产物 H+CO(2 逃避实验测量。我们的结果与 Continetti 小组使用新的低温冷却光电离-光碎片符合装置报告的几乎所有实验数据都非常吻合。
