金属团簇极化性质及其与吸附分子相互作用的研究

项目名称： 金属团簇极化性质及其与吸附分子相互作用的研究

项目编号： No.11204240

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 物理学I

项目作者： 马丽

作者单位： 西北大学

项目金额： 25万元

中文摘要： 团簇使我们可以在纳米尺度范围内，对体系进行精细的以单原子为单位的分析和表征。本项目提出一种新的方法，从单原子角度来研究金属团簇的极化性质，即团簇对静态外电场的响应。不仅要研究团簇的整体响应性质，也就是团簇的总体极化性质；而且要更深入的分析团簇局域的以及特定位置的响应性质。并将这种方法扩展到对不同的同质和异质团簇（包括合金元素）及纳米颗粒的研究。同时研究团簇与吸附分子的化学相互作用，将其与原子尺度分析有限体系响应性质相结合，寻找两者之间存在的内在关系，从而利用特定位置极化来预测团簇的最佳成键位置，为团簇与吸附分子（尤其是极性分子）的相互作用提供指导。此课题对不同尺寸，尤其是较大尺寸金属团簇的催化行为具有一定的理论指导意义。

中文关键词： 金属团簇；极化性质；化学吸附；催化作用；特定位置极化

英文摘要： Atomic clusters allow for a detailed, atomic level analysis and characterization of various system properties at the nanoscale. In this proposal, we formulate a new scheme to study the polarizability of metal cluster, which is a measure of the response of a system to an external electric field. The scheme allows for partitioning of the total polarizability of a cluster into nonoverlapping contributions from its constituent atoms or groups of atoms. Our motivation is to look beyond the global response properties, as captured by the total cluster polarizability, and analyze the local, site-specific responses. We will apply this scheme to a broad variety of clusters of different materials and sizes. At the same time, the reactivities of clusters with adsorption molecules are studied. The site specific analysis of cluster polarizability will be used to investigate the correlation between adsorption energy at various binding sites and the corresponding site polarizabilities. The purpose is to use the site specific polarizabilities as a predictor of optimal binding sites and bonding arrangements. It will be interesting to test the utility of site-specific polarizabilities for identifying promising binding sites in a wider array of contexts. Furthermore,the study will be a new electronic structure tool to explore clust

英文关键词： metal cluster；polarizability；chemisorption；catalysis；site specific polarize