The Chapman cycle, proposed in 1930, describes the various steps in the ongoing formation and destruction of stratospheric ozone. A key step in the formation process is the stabilization of metastable ozone molecules through collisions with a third body, usually an inert collider such as N2. The "ozone isotopic anomaly" refers to the observation of larger-than-expected atmospheric concentrations for certain ozone isotopologues. Previous studies point to the formation steps as the origin of this effect. A possibly key aspect of the ozone formation dynamics is that of the relative efficiencies of the collisional cooling of different isotopologues. Although the substitution of low-abundance 18O for 16O in O3 molecules corresponds to a relatively small net change in mass, related to this are some subtleties due to symmetry-breaking and a resulting more than doubling of the density of allowed states governed by nuclear-spin statistics for bosons. Recently, a highly accurate 3D potential energy surface (PES) describing O3-Ar interactions has been constructed and used to benchmark the low-lying rovibrational states of the complex. Here, using this new PES, we have studied the collisional energy-transfer dynamics using the MultiConfiguration Time Dependent Hartree method. A study of the rotationally inelastic scattering was performed for the parent 16O16O16O-Ar system and compared with that of the 16O16O18O-Ar isotopologue. The state-to-state cross-sections and rates from the 00,0 initial state to low lying excited states are reported. Analysis of these results yields insight into the interplay between small changes in the rotational constants of O3 and the reduced mass of the O3-Ar collision system, combined with that of the symmetry-breaking and introduction of a new denser manifold of allowed states.

中文翻译：

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O3-Ar的旋转非弹性散射：状态-状态速率与多配置时间相关的Hartree方法。

1930年提出的查普曼循环描述了平流层臭氧持续形成和破坏的各个步骤。形成过程中的关键步骤是通过与第三体（通常是惰性对撞机，例如N2）的碰撞来稳定亚稳臭氧分子。“臭氧同位素异常”是指观察到的某些臭氧同位素分子的大气浓度大于预期。先前的研究指出形成步骤是这种效应的起源。臭氧形成动力学的一个可能关键方面是不同同位素分子的碰撞冷却的相对效率。尽管将O3分子中的16O替换为低丰度18O对应于相对较小的质量净变化，与此相关的是由于对称性破坏以及玻色子核自旋统计所控制的允许国家的密度增加了一倍以上而导致的一些微妙之处。最近，已经构建了描述O3-Ar相互作用的高精度3D势能面（PES），并将其用于对复合体的低层旋转振动状态进行基准测试。在这里，我们使用这种新的PES，使用MultiConfiguration Time Dependent Hartree方法研究了碰撞能量转移动力学。对母体16O16O16O-Ar系统进行了旋转非弹性散射的研究，并将其与16O16O18O-Ar同位素体进行了比较。报告了从00,0初始状态到低激发态的状态间横截面和速率。