Kinetics of Ordering for Surface Phase Transitions

埃克森公司的Unertl教授和Liang博士将使用掠入射x射线散射、低能量选择衍射和扫描隧道显微镜来确定表面相变的有序动力学。测量结果将与最近关于模式形成和普遍尺度行为的理论预测进行比较，包括；描述了区域增长、普适类的存在和散射函数的标度性质、基态简并和对称性的影响以及表面缺陷所施加的限制。如果得到证实，这些预测将允许在不同系统中广泛的成核和生长现象得到简单的表征。可以更好地理解非晶材料快速淬火的工艺过程，包括薄膜的烧结、激光熔化后的凝固以及非晶材料的稳定性。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。

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.