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.

埃克森公司的Unertl教授和Liang博士将利用掠入射X射线散射、低能电子衍射和扫描隧道显微镜来确定表面相变的有序动力学。 这些测量结果将与最近关于图案形成和通用缩放行为的理论预测进行比较，包括：对域增长的描述、普遍性类的存在和散射函数的缩放特性、对基态简并和对称性影响的描述以及表面缺陷所施加的限制。 如果这些预测得到验证，将能够简单地表征不同系统中的各种成核和生长现象。 可以更好地理解薄膜中的烧结、激光熔化后的凝固以及快速淬火非晶材料的稳定性等技术过程。 待研究的模型体系包括Au(110)、Pb/Cu(110)、Pb/Cu(001)和Se/Ni(001)。 实验将包括使用布鲁克海文国家实验室的国家同步加速器光源。