Oszlányi Gábor, Süto András
Research Institute for Solid State Physics and Optics of the Hungarian Academy of Sciences, POB 49, H-1525 Budapest, Hungary.
Acta Crystallogr A. 2008 Jan;64(Pt 1):123-34. doi: 10.1107/S0108767307046028. Epub 2007 Dec 21.
This paper summarizes the current state of charge flipping, a recently developed algorithm of ab initio structure determination. Its operation is based on the perturbation of large plateaus of low electron density but not directly on atomicity. Such a working principle radically differs from that of classical direct methods and offers complementary applications. The list of successful structure-solution cases includes periodic and aperiodic crystals using single-crystal and powder diffraction data measured with X-ray and neutron radiation. Apart from counting applications, the paper mainly deals with algorithmic issues: it describes and compares new variants of the iteration scheme, helps to identify and improve solutions, discusses the required data and the use of known information. Finally, it tries to foretell the future of such an alternative among well established direct methods.
本文总结了电荷翻转的现状，电荷翻转是一种最近开发的从头算结构测定算法。其操作基于对低电子密度大平台的扰动，而不是直接基于原子性。这种工作原理与经典直接法的原理截然不同，并提供了互补的应用。成功的结构解析案例包括使用X射线和中子辐射测量的单晶和粉末衍射数据的周期性和非周期性晶体。除了计数应用外，本文主要讨论算法问题：描述和比较迭代方案的新变体，帮助识别和改进解决方案，讨论所需数据和已知信息的使用。最后，它试图预测这种替代方法在成熟的直接法中的未来。
