Ceguerra Anna V, Moody Michael P, Powles Rebecca C, Petersen Timothy C, Marceau Ross K W, Ringer Simon P
School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Australia.
Acta Crystallogr A. 2012 Sep;68(Pt 5):547-60. doi: 10.1107/S0108767312025706. Epub 2012 Jul 20.
The generalized multicomponent short-range order (GM-SRO) parameter has been adapted for the characterization of short-range order within the highly chemically and spatially resolved three-dimensional atomistic images provided by the microscopy technique of atom-probe tomography (APT). It is demonstrated that, despite the experimental limitations of APT, in many cases the GM-SRO results derived from APT data can provide a highly representative description of the atomic scale chemical arrangement in the original specimen. Further, based upon a target set of the GM-SRO parameters, measured from APT experiments, a Monte Carlo algorithm was utilized to simulate statistically equivalent atomistic systems which, unlike APT data, are complete and lattice based. The simulations replicate solute structures that are statistically consistent with other correlation measures such as solute cluster distributions, enable more quantitative characterization of nanostructural phenomena in the original specimen and, significantly, can be incorporated directly into other models and simulations.
广义多组分短程有序(GM-SRO)参数已被用于表征原子探针层析成像(APT)显微镜技术所提供的高度化学和空间分辨的三维原子图像中的短程有序。结果表明,尽管APT存在实验局限性,但在许多情况下,从APT数据得出的GM-SRO结果能够对原始样品中的原子尺度化学排列提供极具代表性的描述。此外,基于从APT实验测量得到的GM-SRO参数目标集,利用蒙特卡罗算法模拟统计等效的原子系统,这些系统与APT数据不同,是完整且基于晶格的。模拟复制的溶质结构在统计上与其他相关度量(如溶质团簇分布)一致,能够对原始样品中的纳米结构现象进行更定量的表征,并且重要的是,可以直接纳入其他模型和模拟中。