The desire to better understand the quantum nature of isomerization led to recent experimental observations of the vibrationally induced isomerization of OC–NaCl(100) to CO–NaCl(100). To investigate the mechanism of this isomerization, we performed dynamics calculations using finite (CO–NaCl)_n cluster models. We constructed new potential energy surfaces for CO–NaCl and CO–CO interactions using high-level ab initio data and report key properties of the bare CO–NaCl potential energy surface, which show much in common with the experiment. We investigated the isomerization dynamics using several cluster models and, in all cases, isomerization was seen for highly excited CO vibrational states, in agreement with experiments. A detailed examination of the reaction trajectories indicates that isomerization occurs when the distance between CO and NaCl is larger than the distance at the conventional isomerization saddle point, which is a strong indicator of ‘roaming’.

为了更好地理解异构化的量子性质，最近对振动诱导的 OC-NaCl(100) 异构化为 CO-NaCl(100) 进行了实验观察。为了研究这种异构化的机制，我们使用有限（CO-NaCl）_{n进行了动力学计算}集群模型。我们使用高级从头算数据为 CO-NaCl 和 CO-CO 相互作用构建了新的势能面，并报告了裸露的 CO-NaCl 势能面的关键性质，这与实验有很多共同之处。我们使用几个集群模型研究了异构化动力学，并且在所有情况下，都观察到高度激发的 CO 振动状态的异构化，这与实验一致。对反应轨迹的详细检查表明，当 CO 和 NaCl 之间的距离大于常规异构化鞍点处的距离时，就会发生异构化，这是“漫游”的有力指标。