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Journal ArticleDOI

Phase annealing in SHELX-90: direct methods for larger structures

George M. Sheldrick
- 01 Jun 1990 - 
- Vol. 46, Iss: 6, pp 467-473
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TLDR
In this article, a phase annealing method, related to the simulated-annealing approach in other optimization problems, is proposed and it is shown that it can result in an improvement of up to an order of magnitude in the chances of solving large structures at atomic resolution.
Abstract
A number of extensions to the multisolution approach to the crystallographic phase problem are discussed in which the negative quartet relations play an important role. A phase annealing method, related to the simulated annealing approach in other optimization problems, is proposed and it is shown that it can result in an improvement of up to an order of magnitude in the chances of solving large structures at atomic resolution. The ideas presented here are incorporated in the program system SHELX-90; the philosophical and mathematical background to the direct-methods part (SHELXS) of this system is described.

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Citations
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Novel approach to phasing proteins: derivatization by short cryo‐soaking with halides

TL;DR: This approach has been tested successfully on four different proteins and has been used to solve the structure of a new protein of molecular weight 30 kDa.
Journal ArticleDOI

Nanoporous metal oxides with tunable and nanocrystalline frameworks via conversion of metal-organic frameworks.

TL;DR: A novel synthetic strategy that exploits a metal-organic framework (MOF)-driven, self-templated route toward nanoporous metal oxides via thermolysis under inert atmosphere is reported, which can be expanded to other nanoporous monometallic and multimetallic oxides with a multitude of potential applications.
Journal ArticleDOI

Blue-emitting iridium complexes with substituted 1,2,4-triazole ligands: synthesis, photophysics, and devices.

TL;DR: The effects of substituents in the 5-position of the triazole ring on the photophysical and electrochemical behavior and the full electrochemical investigation of FIrpic in different solvents are investigated.
Journal ArticleDOI

Alternating Ferromagnetic−Antiferromagnetic Interactions in a Manganese(II)−Azido One-Dimensional Compound: [Mn(bipy)(N3)2]

TL;DR: An alternating di-(μ-(end-on)azido)−di-(mend-to-end)azide) manganese (II) compound, with formula [Mn(bipy)(N3)2] (Bipy = 2,2‘-bipyridine), has been synthesized and characterized as mentioned in this paper.
Journal ArticleDOI

Practical suggestions for better crystal structures

TL;DR: In more complex cases, such as structures with disorders, pseudo-symmetry or twinning, crystallographic knowledge, refinement skills and experience are still vital for obtaining high-quality, publication-grade crystal structures as mentioned in this paper.
References
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Book

Crystallographic Computing 3: Data Collection, Structure Determination, Proteins and Databases

TL;DR: The latest in a series on crystallographic computing, this collection of 33 papers covers the full spectrum of computer applications in crystallography, including the use of micro-, mini-, and mainframe computers.