Hydrogen migration plays an important role in the chemistry of hydrocarbons which considerably influences their chemical functions. The migration of one or more hydrogen atoms occurring in hydrocarbon cations has an opportunity to produce the simplest polyatomic molecule, i.e. H₃⁺. Here we present a combined experimental and theoretical study of H₃⁺ formation dynamics from ethane dication. The experiment is performed by 300 eV electron impact ionization of ethane and a pronounced yield of H₃⁺ + C₂H₃⁺ coincidence channel is observed. The quantum chemistry calculations show that the H₃⁺ formation channel can be opened on the ground-state potential energy surface of ethane dication via transition state and roaming mechanisms. The ab initio molecular dynamics simulation shows that the H₃⁺ can be generated in a wide time range from 70 to 500 fs. Qualitatively, the trajectories of the fast dissociation follow the intrinsic reaction coordinate predicted by the conventional transition state theory. The roaming mechanism, compared to the transition state, occurs within a much longer timescale accompanied by nuclear motion of larger amplitude.

氢迁移在碳氢化合物的化学中起着重要的作用，这极大地影响了它们的化学功能。烃阳离子中一个或多个氢原子的迁移有机会产生最简单的多原子分子，即H ₃ ⁺。_{在这里，我们提出了乙烷双阳离子 H 3} ⁺形成动力学的综合实验和理论研究。该实验通过乙烷的 300 eV 电子碰撞电离进行，观察到 H ₃ ⁺ + C ₂ H ₃ ⁺重合通道的显着产率。量子化学计算表明，H ₃ ⁺可以通过过渡态和漫游机制在乙烷双阳离子的基态势能面上打开形成通道。从头算分子动力学模拟表明，H ₃ ⁺ 可以在70至500 fs的较宽时间范围内产生。定性地，快速解离的轨迹遵循传统过渡态理论预测的本征反应坐标。与过渡态相比，漫游机制发生在更长的时间尺度内，伴随着更大幅度的核运动。