Kinetics of Ordering for Surface Phase Transitions

表面相变有序动力学

• 批准号: 8803529
• 负责人: William Unertl
• 金额: $ 22.35万
• 依托单位: University of Maine
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-05-01 至 1991-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8803529&HistoricalAwards=false
• 关键词: Kinetics; Ordering; Surface; Phase; Transitions

Professor Unertl and Dr. Liang, Exxon Corp., will use grazing incidence x-ray scattering, low energy election diffraction and scanning tunneling microscopy to determine the kinetics of ordering for surface phase transitions. The measurements will be compared with recent theoretical predictions about pattern formation and universal scaling behavior including; a description of domain growth, the existence of universality classes and the scaling properties of scattering functions, the description of effects of ground state degeneracy and symmetry, and the limitations imposed by surface imperfections. If validated these predictions will permit a wide range of nucleation and growth phenomena in diverse systems to be characterized simply. Technological processes including sintering in then films, solidification following laser melting, and the stability of rapidly quenched amorphous materials can be better understood. The model systems to be studied include Au(110), Pb/Cu(110), Pb/Cu(001), and Se/Ni(001). Experiments will include the use of the National Synchrotron Light Source at Brookhaven National Laboratory.

Exxon Corp.的Unertl教授和Liang博士将使用放牧的发病率X射线散射，低能选举衍射和扫描隧道显微镜来确定表面相变的订购动力学。 测量结果将与有关模式形成和普遍缩放行为的最新理论预测进行比较。描述了域的生长，普遍性的存在以及散射函数的缩放特性，基态堕落和对称性的影响的描述以及表面缺陷所施加的局限性。 如果经过验证，这些预测将允许简单地表征各种系统中的各种成核和生长现象。 可以更好地理解技术过程，包括当时的膜，激光熔化后的固化以及快速淬火的无定形材料的稳定性。 要研究的模型系统包括AU（110），PB/CU（110），PB/CU（001）和SE/Ni（001）。 实验将包括在布鲁克黑文国家实验室使用国家同步器光源。