Presidential Young Investigator Award

总统青年研究员奖

• 批准号: 9158584
• 负责人: James Adams
• 金额: $ 21万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-08-01 至 1997-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9158584&HistoricalAwards=false
• 关键词: Presidential; Young; Investigator; Award

Two projects will be initiated on this PYI grant: one involves improving ab-initio tight binding code for electronic structure and the other deals with pre-melting at surfaces. In the first project, the proposed code improvements using localized orbitals promise extremely fast calculations of the molecular dynamics of systems with up to 200 atoms. The method can presently handle s- and p-orbitals, but will be expanded to deal with d-orbitals so that transition element properties can be calculated. The improved code will be used to study adhesion at polymer-metal interfaces and the structure of nanoscale metallic clusters. The study of pre- melting of surfaces will focus on lead. The effective atom method will be used to calculate the Gibbs free energy of the bulk solid and the bulk liquid; the melting point will be obtained from this information. For a range of temperatures below the melting point molecular dynamics will be used to simulate several lead surfaces. %%% On this Presidential Young Investigator grant two projects in theoretical materials science will be initiated. The first will involve the improvement of a computer code to deal with transition metals which are important in many applications. This improved code will then be used to study adhesion at polymer-metal interfaces and the structure of nanoscale metal clusters. The study of the pre-melting of lead surfaces will improve our understanding of why the surfaces of metals often melt prior to the melting of the bulk materials. This has important ramifications in the processing of metals for a variety of applications.

保华计划将利用拨款开展两项计划： 改进了电子结构的从头算紧束缚码， 另一个涉及表面的预熔化。 上 项目，建议使用本地化轨道的代码改进 保证了分子动力学的快速计算， 最多有200个原子。 该方法目前可以处理S- 和p轨道，但将扩展到处理d轨道， 可以计算过渡元素的性质。 改进的 代码将用于研究聚合物-金属界面处的粘附性， 纳米金属簇的结构。 研究预- 表面的熔化将集中在铅上。 有效原子法 将用于计算散装固体的吉布斯自由能 和散装液体;熔点将获得从这个 信息. 对于低于熔点的温度范围 分子动力学将被用来模拟几个铅表面。 %%% 在这个总统青年研究员赠款两个项目， 理论材料科学将被启动。 第一个将 包括改进计算机代码来处理过渡 在许多应用中很重要的金属。 这种改进 代码将被用来研究粘附在聚合物-金属 界面和纳米金属簇的结构。 的 研究铅表面的预熔化将提高我们的 理解为什么金属表面经常在熔化之前熔化， 散装材料的熔化。 这在以下方面具有重要的影响： 用于各种应用的金属加工。