Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands.
Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands.
Nat Chem. 2018 May;10(5):549-554. doi: 10.1038/s41557-018-0015-x. Epub 2018 Apr 9.
Collision-induced absorption is the phenomenon in which interactions between colliding molecules lead to absorption of light, even for transitions that are forbidden for the isolated molecules. Collision-induced absorption contributes to the atmospheric heat balance and is important for the electronic excitations of O that are used for remote sensing. Here, we present a theoretical study of five vibronic transitions in O-O and O-N, using analytical models and numerical quantum scattering calculations. We unambiguously identify the underlying absorption mechanism, which is shown to depend explicitly on the collision partner-contrary to textbook knowledge. This explains experimentally observed qualitative differences between O-O and O-N collisions in the overall intensity, line shape and vibrational dependence of the absorption spectrum. It is shown that these results can be used to discriminate between conflicting experimental data and even to identify unphysical results, thus impacting future experimental studies and atmospheric applications.
碰撞诱导吸收是一种现象，即分子之间的相互作用导致光的吸收，即使对于孤立分子来说是禁止的跃迁也是如此。碰撞诱导吸收对大气热平衡有贡献，对用于遥感的 O 的电子激发也很重要。在这里，我们使用分析模型和数值量子散射计算对 O-O 和 O-N 中的五个振转跃迁进行了理论研究。我们明确地确定了潜在的吸收机制，结果表明该机制明确取决于碰撞伙伴，这与教科书上的知识相反。这解释了实验中观察到的 O-O 和 O-N 碰撞在吸收光谱的整体强度、线型和振动依赖性方面的定性差异。结果表明，这些结果可用于区分相互矛盾的实验数据，甚至可以识别不真实的结果，从而影响未来的实验研究和大气应用。
