JILA, University of Colorado and National Institute of Standards and Technology, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0440, USA.
Phys Chem Chem Phys. 2010 Nov 14;12(42):14294-308. doi: 10.1039/c0cp00578a. Epub 2010 Oct 1.
Full three dimensional (3D) translational distributions for quantum state-resolved scattering dynamics at the gas-liquid interface are presented for experimental and theoretical studies of CO(2) + perfluorinated surfaces. Experimentally, high resolution absorption profiles are measured as a function of incident (θ(inc)) and scattering (θ(scat)) angles for CO(2) that has been scattered from a 300 K perfluorinated polyether surface (PFPE) with an incident energy of E(inc) = 10.6(8) kcal mol(-1). Line shape analysis of the absorption profiles reveals non-equilibrium dynamics that are characterized by trapping-desorption (TD) and impulsive scattering (IS) components, with each channel simply characterized by an effective "temperature" that compares very well with previous results from rotational state analysis [Perkins and Nesbitt, J. Phys. Chem. A, 2008, 112, 9324]. From a theoretical perspective, molecular dynamics (MD) simulations of CO(2) + fluorinated self-assembled monolayer surface (F-SAMs) yield translational probability distributions that are also compared with experimental results. Trajectories are parsed by θ(scat) and J, with the results rigorously corrected by flux-to-density transformation and providing comparisons in near quantitative agreement with experiment. 3D flux and velocity distributions obtained from MD simulations are also presented to illustrate the role of in- and out-of-plane scattering.
呈现了用于实验和理论研究 CO(2) + 全氟表面的量子态分辨散射动力学的完全三维(3D)平移分布。在实验中,作为 CO(2) 的散射角度θ(inc)和散射角度θ(scat)的函数,测量了具有入射能量 E(inc) = 10.6(8) kcal mol(-1)的 300 K 全氟聚醚表面 (PFPE) 的 CO(2) 的高分辨率吸收轮廓。吸收轮廓的线形状分析揭示了非平衡动力学,其特征在于俘获-解吸 (TD) 和脉冲散射 (IS) 分量,每个通道都简单地用有效“温度”来表征,与先前的旋转态分析结果非常吻合[Perkins 和 Nesbitt,J. Phys. Chem. A,2008,112,9324]。从理论角度来看,CO(2) + 氟化自组装单分子层表面 (F-SAMs) 的分子动力学 (MD) 模拟产生了平移概率分布,也与实验结果进行了比较。轨迹根据θ(scat)和 J 进行解析,结果通过通量到密度的转换进行严格校正,并与实验进行了近乎定量的比较。还呈现了从 MD 模拟获得的 3D 通量和速度分布,以说明平面内和平面外散射的作用。