论文标题
对低能量No-H $ _2 $碰撞的共振的实验和理论调查
Experimental and Theoretical Investigation of Resonances in Low-Energy NO-H$_2$ collisions
论文作者
论文摘要
事实证明，低能碰撞中散射共振的实验表征是对量子化学计算的严格测试。 No-H $ _2 $系统的先前测量值降低至$ 10 $ CM $^{ - 1} $对可用势能表面的最复杂计算提出了质疑。在本报告中，我们通过在先前未开发的$ 0.4-10 $ cm $^{ - 1} $区域中测量No-H $ _2 $系统的散射行为来继续进行这些调查。我们研究了\ textit {para} - 和\ textit {ortho} -h $ _2 $在交叉分子束实验中，涉及Stark减速和速度图成像的\ textit {ortho} -h $ _2 $的国家特异性非弹性碰撞。我们能够在测得的积分和差分横截面中解析共振特征。将结果与来自两个先前可用的势能表面的预测进行了比较，我们能够明确区分两个电位。我们还确定了对这些共振的部分波贡献，并研究与\ textit {para} - 和\ textit {ortho} -h $ _2 $相撞之间差异的性质。此外，我们调整了实验中的能量扩散，以使我们的优势在超出平均实验极限之外的能量上探测散射行为。
The experimental characterization of scattering resonances in low energy collisions has proven to be a stringent test for quantum chemistry calculations. Previous measurements on the NO-H$_2$ system at energies down to $10$ cm$^{-1}$ challenged the most sophisticated calculations of potential energy surfaces available. In this report, we continue these investigations by measuring the scattering behavior of the NO-H$_2$ system in the previously unexplored $0.4 - 10$ cm$^{-1}$ region for the parity changing de-excitation channel of NO. We study state-specific inelastic collisions with both \textit{para}- and \textit{ortho}-H$_2$ in a crossed molecular beam experiment involving Stark deceleration and velocity map imaging. We are able to resolve resonance features in the measured integral and differential cross sections. Results are compared to predictions from two previously available potential energy surfaces and we are able to clearly discriminate between the two potentials. We furthermore identify the partial wave contributions to these resonances, and investigate the nature of the differences between collisions with \textit{para}- and \textit{ortho}-H$_2$. Additionally, we tune the energy spreads in the experiment to our advantage to probe scattering behavior at energies beyond our mean experimental limit.
