Table of Contents
The CCP14 Project: - software for X-ray diffraction analysts.
Notes Free Zone - they are on the web - http://www.ccp14.ac.uk/poster-talks/axaa2002/
Aims of the EPSRC funded CCP14 Project
The risks of not knowing what you don’t know
Why bother knowing about a variety of X-ray diffraction software
Why bother knowing about a variety of MODERN software?
Why bother looking into diffraction techniques you have not tried before?
What do we need from the diffraction data in this geosciences example?
Solution for mass unit cell refinement of data with overlapping peaks, multiple phases, etc, etc.
Using the right crystallographic method can make the difference!
Rietica: results of the volume of Oxygen and the earth’s other core
Phase Identification/Search Match for Powder Diffraction
Phase Identification/Search Match for Powder Diffraction 2 of 3 - Identifying an organic - DL-Valine
Phase Identification/Search Match for Powder Diffraction 3 of 3 - Multiphase mixture: Flourite, Corundum, Zincite
Sample Preparation and Data Collection
Variable Count Time data collection
VCT Literature References
VCT for trace Phase ID (1 of x) - Fixed Count Time data - (data collected by Jeremy Cockcroft)
VCT for trace Phase ID (1 of x) - Variable Count Time data (displayed as FCT) - (data collected by Jeremy Cockcroft)
VCT for trace Phase ID (1 of x) - Fixed Count Time data (zoomed) -
VCT for trace Phase ID (1 of x) - Variable Count Time data (displayed as FCT) -
Variable Count Time applications
VCT to aid in profile fitting (1 of 3) - Fixed Count Time -
VCT to aid in profile fitting (2 of 3) - Variable Count Time -
VCT to aid in profile fitting (3 of 3) - Overlaying VCT and FCT -
VCT Data Collection Strategies?
Where is VCT Data Collection?
Has the structure been solved already? - Crystallographic Structure Databases
ICSD via the Web
Powder Data Conversion / Importing Data
Structure Importing, Conversion and Transformation
Powder Diffraction Utility Software
Peak Profiling - (indexing, unit cell refinement, size/strain, etc)
Peak Profiling: Crystallite size and strain using Fundamental Parameters peak profiling in XFIT
XFIT Fundamental Parameters peak profiling compared to empirical Peak Fitting - Powder Indexing FOM Results
Peak Profiling and Analysis using WinFIT by Stefan Krumm - (profile fitting, size/strain analysis)
Powder Indexing - a non trivial endeavour
Powder Indexing - the "Crysfire" suite
Chekcell: Interpreting Crysfire Summary Files: - Powder Indexing and Spacegroup Assignment
Chekcell : automatic cell and spacegroup searching
Chekcell: "integration" of Ton Spek and A. Meetsma’s Le Page
Chekcell: GUI Cell transformation
Chekcell: example of using Le Page
Why doesn’t this powder sample index?
Some Alternatives to Crysfire: Winplotr, PowderX
Unit Cell Refinement
Unit Cell Refinement - what is needed
CELREF for Unit Cell Refinement
Using CELREF for Unit Cell Refinement - Loading the raw data file (optional)
Using CELREF for Unit Cell Refinement - Loading the peak listing file
Using CELREF for Unit Cell Refinement - Load or input the cell and spacegroup
Using CELREF for Unit Cell Refinement - Auto-match peak positions to HKLs
Using CELREF for Unit Cell Refinement - Perform the refinement
CELREF for Unit Cell Refinement on one phase in a multiphase sample
UNITCell refinement with internal standard - (such as NBS/NIST Silicon)
UNITCell refinement : fundamental parameters fitting vs empirical fitting
Full Profile Fitting (Powder)
Rietica Rietveld - Le Bail full profile fitting
Le Bail full profile fitting - Rietica Rietveld - 2 of 2
Unit Cell Refinement: Mass Le Bail fitting: multi-phase - overlapping patterns
Le Bailing fitting : Knowing the limitations! - Synchrotron data with position calibration problems
Le Bail full profile fitting on standard laboratory data
Materials Analysis Rietveld/Texture Software
Structure Refinement using Powder Diffraction Data - (Rietveld Refinement)
Rietveld Programs - Rietica by Brett Hunter
Mentioning GSAS Rietveld: Some Relevant Background
GSAS : Solving and refining a protein from powder data
GSAS : Combined refinement on both XRD and Neutron
Brian Toby’s EXPGUI Interface for GSAS
MAUD for Java : GPL’d - can be used by all!
Rietveld: Rod Hill and Ian Madsen VCT data collection
Quantitative Phase Analysis
For trace quantitative analysis, variable count time on the trace peaks that matter could be beneficial - if your data collection software allows you to.
Peak profiling on trace peaks is difficult with fixed count time! Same goes with Rietveld fitting of trace phases.
pThus Peak profiling on trace peaks can be made easier by using Variable Count time methods
Quantitative Phase Analysis - is it routinely easy?
Powder diffraction pattern calculation - Poudrix for Windows
Powder diffraction pattern calculation - Powder Cell for Windows
Simulating multiple phase patterns with Powder Cell
Simulating multiple phase patterns with Powder Cell - Open the phase / crystal structure using File Load: - (in this case : anatase and rutile)
Change the diffraction conditions as required using the "Diffraction, Experiment" menu
At this point, what would the diffraction pattern of 1% Anatase in Rutile look like - use the "Diffraction Phase Options"
Then OK to calculate the diffraction pattern of 1% Anatase in Rutile
Then OK to calculate the diffraction pattern of 1% Anatase in Rutile : zoomed data
Then OK to calculate the diffraction pattern of 1% Anatase in Rutile : change Number of Half Widths
Then OK to calculate the diffraction pattern of 1% Anatase in Rutile : Recalculate
"Freeware" for photorealistic hardcopy output of structures - GRETEP and Povray
GRETEP - rendered structure
Struplo for for Windows by Louis Farrugia - Freeware Polyhedral Structure Drawings
Freeware for photorealistic hardcopy output of structures - Struvir by Armel Le Bail for Polyhedral Structure Drawings via VRML (Virtual Reality Modeling Language)
Freeware for photorealistic hardcopy output of structures - Balls and Sticks by Sung J. Kang & Tadashi C. Ozawa
Dual Boot UNIX / Windows PC and Crystallographic Nexus CD-ROMs for those isolated from the internet
Some Other Web Resources
Author: Lachlan Cranswick, CCP14 Project, School of Crystallography, Birkbeck University of London, UK.
Home Page: http://www.ccp14.ac.uk
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