Europe
David Rafaja
Freiberg University of
Mining and Technology
Germany
[email protected]
www.tu-freiberg.de/allgemein/international/
or www.ww.tu-freiberg.de/~rafaja/
Current Trends in Materials Science
Related to Powder Diffraction
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Investigation of the influence of the real structure
and microstructure on the physical (mechanical,
electrical, magnetic, optical, thermal) properties of
matters
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Application of the Rietveld method to the real
structure and microstructure analysis
Real Structure
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Phase composition
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Lattice parameters, fractional coordinates and
thermal vibrations of atoms  Inter-atomic distances
 Energy bands  Changes in the electronic,
optical and magnetic properties
Microstructure
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Preferred orientation of crystallites  Enhancement
of the crystal anisotropy
Crystallite size and shape  Scattering centers for
electrons
Structural defects (Dislocations, Stacking faults,
Disclinations = local lattice rotations)  Scattering
centers for electrons
Residual stress  Anisotropic changes in the interatomic distances
Rietveld-like Routines
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J. Rodriguez-Carvajal: FULLPROF (structure refinement,
quantitative analysis, simplified line profile analysis, magnetic
structures)
R. von Dreele: GSAS (structure refinement, quantitative
analysis and stress/strain analysis)
V. Petricek: JANA (structure refinement also for
incommensurate structures)
J. Bergmann: BGMN (structure refinement, quantitative
analysis and stress/strain analysis)
L. Lutterotti: MAUD (structure refinement, quantitative analysis
and stress/strain/site analysis)
V. Favre-Nicolin and R. Cerny: FOX (crystal structure solution
from powder diffraction by Simulated Annealing Monte Carlo
method)
Recent Own Results
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Diffraction phenomena (coherence effects) in
nanocrystalline materials
The XRD recognizes larger crystallites (because of
their mutual coherence) and larger microstrain
(because of the structure defects at the crystallite’s
boundaries) than they really are
These phenomena are pronounced in
nanocrystalline materials with a strong preferred
orientation
Recent Own Results
Neighboring crystallites are
fully coherent
Partly coherent
Non-coherent
0.045
-1
Line width (Å )
0.040
0.035
1
0.030
0.5
0.025
0
0.020
-0.5
0.015
-1
-1
-0.5
0
0.5
0.010
0
7
2
4
6
8
-1
q = 4*pi*sin  /  [Å ]
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1
Trends in support of science
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EU projects
Government projects
Grant agencies
Foundations
Industry
Institutional resources
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Information technologies
New materials
New technologies
Basic research
The resources are assigned to the specific problems of the project.
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Databases (in Germany) can be paid either from institutional
resources (budget) or from the profit of the service
European Conferences 2004
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Best Practice Strategies to Identify, Characterize & Control
Polymorphism & Crystallization, London, UK, April 21-22, 2004
2nd International Conference on High Performance Structures
and Materials (HPSM 2004), Ancona, Italy, May 31 – June 2,
2004,
http://www.wessex.ac.uk/conferences/2004/hpsm2004/3.html
VII International School and Symposium on Synchrotron
Radiation in Natural Science, Zakopane, Poland, June 8-13,
2004, http://issrns04.us.edu.pl/
Electron Crystallography: Novel Approaches to Structure
Determination of Nanosized Materials, Erice, Italy, June 9-20,
2004, http://www.crystalerice.org/2004/ElCryst2004.htm
European Conferences 2004
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2nd International Conference on Texture and Anisotropy of
Polycrystals (ITAP2), Metz, France, July 7-9, 2004,
http://194.57.144.1/ITAP2/Itap2_acceuil.htm
Multifunctional and Functionally Graded Materials (FGM2004),
Leuven, Belgium, July 11-14, 2004, http://www.fgm2004.com
Diffusion in Materials (DIMAT 2004), Krakow, Poland, July 1823, 2004, http://www.dimat2004.agh.edu.pl/
The 20th General Conference of the Condensed Matter Division
of the European Physical Society, Prague, Czech Republic,
July 19-23, 2004, http://cmd.karlov.mff.cuni.cz/CMD/
European Conferences 2004
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ECM-22, Budapest, Hungary, August 26-31, 2004,
http://www.ecm22.mtesz.hu/
EPDIC-9, Prague, Czech Republic, September 2-5, 2004,
http://www.xray.cz/epdic/
Size/Strain and Quantitative Phase Analysis Software
Workshop (Satellite Meeting of the EPDIC-9), Prague, Czech
Republic, September 2, 2004,
http://lachlan.bluehaze.com.au/epdic-2004/
Size-Strain IV (Satellite Meeting of the EPDIC-9), Prague,
Czech Republic, August 31 – September 2, 2004,
http://www.xray.cz/s-s4/
European Conferences 2004
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7th Biennial Conference on High Resolution X-Ray Diffraction
and Imaging (X-TOP), Prague, Czech Republic, September 710, 2004, http://www.xray.cz/xtop/
4th International Conference on Inorganic Materials, Antwerp,
Belgium, September 19-21, 2004, http://www.imconference.com
Symposium on Texture and Microstructure Analysis of
Functionally Graded Materials (SOTAMA-FGM), Krakow,
Poland, October 3-7, 2004,
http://www.namam.krakow.pl/sotama/
European Conferences 2005
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International Conference on Textures of Materials (ICOTOM
14), Leuven, Belgium, July 11-15, 2005,
http://www.icotom14.com
XX Congress of IUCr, Florence, Italy, August 23-31, 2005,
http://www.iucr2005.it
Role of the Powder Diffraction File
Phase Analysis
Building of a Microstructure Model
(structure data are necessary)
Rietveld Refinement
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