Journal ArticleDOI
Phase annealing in SHELX-90: direct methods for larger structures
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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.read more
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Complete relative stereochemistry of multiple stereocenters using only residual dipolar couplings.
Jiangli Yan,Frank Delaglio,Andreas Kaerner,Allen D. Kline,Huaping Mo,Michael J. Shapiro,Tim A. Smitka,Gregory A. Stephenson,Edward R. Zartler +8 more
TL;DR: Residual dipolar couplings (RDCs), in combination with molecular order matrix calculations, were used to unambiguously determine the complete relative stereochemistry of an organic compound with five stereocenters, and it was shown that (13)C-H and (1)H-(1) H RDCs, which are the easiest to measure, are the most important and information-rich data for the order matrix calculation.
Journal ArticleDOI
Steric Influence on the Reactivity of the (o-Carboranedithiolato)iridium(III) Complex [Ir(η5-C5Me5)(η2-S2C2B10H10)]: New Types of Addition Reactions Involving Cyclometalation or Isomerization†
TL;DR: In this article, the reactivity of the mononuclear 16-electron iridadithiolene ring complex Cp*Ir(S2C2B10H10) (1) toward alkynes, a diazoalkane, and quadricyclane has been investigated.
Journal ArticleDOI
A series of metal–organic polymers assembled from MCl2 (M = Zn, Cd, Co, Cu): structures, third-order nonlinear optical and fluorescent properties
TL;DR: It is demonstrated that metal ions play an important part in the NLO and fluorescent properties of coordination polymers and both 2 and 3 show similar NLO properties to fcz.
Journal ArticleDOI
Complex Crystal Structure of Cesium-III
TL;DR: The structure of Cs-III, stable between 4.2 and 4.3 GPa at room temperature, has been determined from single-crystal x-ray diffraction data and is a complex new type of elemental structure which is orthorhombic (space group C222(1)) with 84 atoms in the unit cell.
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Nonlinear optical properties, spectroscopic studies and structure of 2-hydroxy-3-methoxy- N-(2-chloro-benzyl)-benzaldehyde-imine
TL;DR: In this article, a 2-hydroxy-3-methoxy-N-(2-chloro-benzyl)-benzaldehyde-imine (C15H14O2NCl) has been synthesized and characterized by elemental analysis, X-ray analysis, IR, 1H-NMR, and UV-Visible spectroscopy.
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.