scholarly journals Analysis of Dickerson dodecamer and several proteins using x-ray anomalous scattering

2014 ◽  
Author(s):  
Shuo Huang
Keyword(s):  
Anomalous Scattering ◽  
X Ray ◽  
Dickerson Dodecamer

CHOOCH: a program for deriving anomalous-scattering factors from X-ray fluorescence spectra

2001 ◽  
Vol 34 (1) ◽  
pp. 82-86 ◽  
Author(s):  
Gwyndaf Evans ◽  
Robert F. Pettifer
Keyword(s):  
Absorption Edge ◽  
Fluorescence Spectra ◽  
Heavy Atom ◽  
Fortran Program ◽  
Anomalous Scattering ◽  
Tabular Data ◽  
X Ray ◽  
Scattering Factor ◽  
Experimental Values ◽  
Kronig Relation

A Fortran programCHOOCH, which derives experimental values of the anomalous-scattering factorsf′′ andf′ from X-ray fluorescence spectra, is described. The program assumes knowledge of theoretical values for the imaginary term,f′′, of the anomalous-scattering factor away from the absorption edge to scale the experimental fluorescence spectrum and thus derive values off′′ near the absorption edge, where tabular data are inappropriate. The Kramers–Kronig relation is used to calculate the real part,f′, of the anomalous-scattering factor. The program aids the decision-making process in macromolecular crystallographic experiments where optimal wavelength selection is required. Magnitudes off′ andf′′ at selected wavelengths can later be used as starting values for heavy-atom refinement with crystallographic phasing programs.

X-ray anomalous scattering and specular reflection inMVphotoabsorption regions

1984 ◽  
Vol 29 (12) ◽  
pp. 6576-6585 ◽  
Author(s):  
J. M. André ◽  
R. Barchewitz ◽  
A. Maquet ◽  
R. Marmoret
Keyword(s):  
Specular Reflection ◽  
Anomalous Scattering ◽  
X Ray

Structures of Co90Fe10/Cu multilayers determined by X-ray anomalous scattering measurements

2006 ◽  
Vol 496 (2) ◽  
pp. 571-575 ◽  
Author(s):  
Y.K. An ◽  
B. Dai ◽  
Z.H. Mai ◽  
J.W. Cai ◽  
Z.H. Wu
Keyword(s):  
Anomalous Scattering ◽  
X Ray ◽  
Scattering Measurements

An instrument for time-resolved and anomalous simultaneous small- and wide-angle X-ray scattering (SWAXS) at NSRRC

2006 ◽  
Vol 39 (6) ◽  
pp. 871-877 ◽  
Author(s):  
Ying-Huang Lai ◽  
Ya-Sen Sun ◽  
U-Ser Jeng ◽  
Jhih-Min Lin ◽  
Tsang-Lang Lin ◽  
...  
Keyword(s):  
Lipid Membrane ◽  
Quantum Wires ◽  
Grazing Incidence ◽  
Anomalous Scattering ◽  
Wide Angle ◽  
Scanning Calorimetry ◽  
Time Resolved ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

A SWAXS (small- and wide-angle X-ray scattering) instrument was recently installed at the wiggler beamline BL17B3 of the National Synchrotron Radiation Research Center (NSRRC), Taiwan. The instrument, which is designed for studies of static and dynamic nanostructures and correlations between the nano (ormeso) structure (SAXS) and crystalline structure (WAXS), provides a flux of 1010–1011photon s−1at the sample at energies between 5 and 14 keV. With a SAXS area detector and a WAXS linear detector connected to two data acquisition systems operated in master–slave mode, the instrument allows one to perform time-resolved as well as anomalous scattering measurements. Data reduction algorithms have been developed for rapid processing of the large SWAXS data sets collected during time-resolved measurements. The performance of the instrument is illustrated by examples taken from different classes of ongoing projects: (i) time-resolved SAXS/WAXS/differential scanning calorimetry (DSC) with a time resolution of 10 s on a semicrystalline poly(hexamethylene terephthalate) sample, (ii) anomalous SAXS/WAXS measurements on a nanoparticulate PtRu catalyst, and (iii) grazing-incidence SAXS of a monolayer of oriented semiconductor quantum wires, and humidity-controlled ordering of Alamethicin peptides embedded in an oriented lipid membrane.

scholarly journals Advances in Synchrotron X-ray Polycrystalline Diffraction

1988 ◽  
Vol 41 (2) ◽  
pp. 101 ◽  
Author(s):  
William Parrish
Keyword(s):  
High Resolution ◽  
Grazing Angle ◽  
Anomalous Scattering ◽  
Wavelength Selection ◽  
High Count ◽  
Instrument Function ◽  
X Ray ◽  
Depth Analysis ◽  
Diffraction Patterns ◽  
New Applications

The advantages of synchrotron radiation for X-ray polycrystalline diffraction are illustrated by a number of examples. The plane wave parallel-beam X-ray optics uses a Si(lll) channel monochromator for easy wavelength selection and a set of long parallel slits to define the diffracted beam. The constant simple instrument function and the high resolution symmetrical profiles (FWHM 0.05") greatly simplify the data analysis and add a new dimension to profile broadening studies. The geometry permits uncoupling the 6-26 sample-detector relationship without changing the profile shape and makes possible new applications such as grazing angle incidence depth analysis of thin films. The same instrumentation is used for high resolution energy dispersive diffraction (BOD) by step-scanning the monochromator. The resolution is two orders of magnitude better than conventional BOD and can be used at high count rates. The easy wavelength selection yields diffraction patterns with the highest PI B and permits anomalous scattering studies.

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