Fully Quantum Studies of Molecule-Surface Interactions at Finite Temperature

这项分子吸附在固体表面的研究得到了美国国家科学基金会理论与计算化学项目的支持。分子-声子相互作用使用哈密顿算符进行量子力学处理，该算符可以包括多个声子，以及分子的受阻平移，旋转和振动模式，以及这些自由度的所有可能的相互作用。弱（单声子）和强（多声子）相互作用都可以被描述。从解吸、弛豫和热原子化学的角度讨论了俘获态的性质。研究了平行于表面的光束能量分量变化的影响。本研究使用计算机模型来研究吸附在固体表面上的分子的运动。目标是获得表面化学原理的基本知识，这反过来又涉及到具有重要实际意义的化学过程，如多相催化。计算机建模是研究这类过程的一种广泛使用的理论工具。本研究项目的特殊作用是测试这些计算中常用的各种数学和物理近似的有效性。特别地，量子力学的定律，而不是经典力学，被应用，和分子与一个或多个声子（量子化晶格振动）的相互作用被处理。

This study of molecules adsorbed on a solid surface is supported by the NSF Theoretical and Computational Chemistry program. The molecule-phonon interaction is treated quantum mechanically using a Hamiltonian operator that can include multiple phonons, as well as the hindered translational, rotational, and vibrational modes of the molecule, and all possible interactions of these degrees of freedom. Both weak (one phonon) and strong (multi-phonon) interactions can be described. The nature of the trapped state with regard to desorption, relaxation, and hot atom chemistry is treated. The effect of varying the component of beam energy parallel to the surface is also studied. Computer models are used in this research to study the motion of molecules adsorbed on solid surfaces. The goal is to gain fundamental knowledge of the principles of surface chemistry, which in turn relates to chemical processes of great practical importance such as heterogeneous catalysis. Computer modeling is a widely used theoretical tool for the study of such processes. The special role of this research project is to test the validity of various mathematical and physical approximations commonly employed in these computations. In particular, the laws of quantum mechanics, rather than classical mechanics, are applied, and the interaction of the molecule with one or more phonons (quantized lattice vibrations) are treated.