Open AccessThe charge flipping algorithm
Author(s) -
Oszlányi Gábor,
Sütő András
Publication year - 2008
Publication title -
acta crystallographica section a
Language(s) - English
Resource type - Journals
eISSN - 1600-5724
pISSN - 0108-7673
DOI - 10.1107/s0108767307046028
Subject(s) - aperiodic graph , computer science , algorithm , atomicity , charge (physics) , ab initio , perturbation (astronomy) , perturbation theory (quantum mechanics) , physics , mathematics , quantum mechanics , programming language , combinatorics , database transaction
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.