Dear all,

The ILL is organising the 2nd Annual School on Advanced Neutron Diffraction
Data Treatment using the FullProf Suite. The registration is already open
and we would like to invite you to submit candidatures and to give the
maximum diffusion in your institutes.

Those interested can find more information in the ILL web site:
http://www.ill.eu/news-events/events/
where the programme is now available.

Many thanks in advance for helping in the diffusion of this information.

Best regards,

The local organizing committee of FPSchool - 2009

Juan RODRIGUEZ-CARVAJAL, [EMAIL PROTECTED]
Marie-Hélène LEMÉE-CAILLEAU, [EMAIL PROTECTED]
Gabriel CUELLO, [EMAIL PROTECTED]
_________________________________________________________________________
FPSchool - 2009
2nd ILL annual school on Advanced Neutron Diffraction Data Treatement
using the FULLPROF Suite
26-30 January 2009
Grenoble, France.

Email: [EMAIL PROTECTED]
URL: http://www.ill.eu/dif/FPSchool/
_________________________________________________________________________


Programme

26/01/2009

1  General introduction to the programs of the FullProf Suite.
Web site: downloading the suite and individual programs.
The use of the FPS_Toolbar for accessing the programs.
Consulting the manuals and documentation.

2  Use of the program WinPLOTR for visualising diffraction patterns, peak
detection and peak fit, exporting background, visualisation of 3D plots,
2D detectors, etc.

3  Indexing powder diffraction patterns (with the indexing programs:
DICVOL04, TREOR-90, etc).

4  Determination of propagation vectors of superstructures and
incommensurate magnetic structures.
Programs: SuperCell and k_Search.

Practical session  Format of diffraction pattern files, superposition of
diffraction patterns using a common scattering variable (Q-space, d-space,
s-space) when the original diffraction patterns are in 2theta-space or
time-of-flight-space. How to save selected peaks and/or background for
indexing programs. Running the programs from the FPS_Toolbar or from
WinPLOTR. The use of EdPCR and text editors. Importing CIF files.



27/01/2009

5  Introduction to the mathematical description of powder diffraction
patterns. Peak shapes.
Instrumental resolution of constant wavelength and time-of-flight neutron
powder diffractometers.
Sample contribution to broadening (microstructure).

6  Refinement of powder diffraction patterns without structural model.
Pawley and Le Bail methods.
Limitations and pitfalls.

7  Ab-initio structure determination using powder diffraction.
Direct methods (XLENS), real-space methods (Monte Carlo and simulated
annealing).

Practical session  Using WINPLOTR for fitting zones of the diffraction
pattern. Setting up an instrumental resolution file. Using the Le Bail
method for extracting integrated intensities. Preparation of integrated
intensity files to be used by the simulated annealing method implemented
in FullProf or for using XLENS. Simple examples of crystal structure
determination.


28/01/2009

8  Introduction to the Rietveld method.
The limitations of the least-squares optimisation method.
Structural models: the expressions of structure factors in the case of
simple crystal structures, magnetic structures, rigid-body, special form
factors. Symmetry-adapted modes. Free parameters of the structural model
and information contained in powder diffraction patterns. Agreement
indices and graphic output.

9  Strategy for Rietveld refinements.
Behaviour of the program under an excess of free parameters.
The use of constraints and restraints.
Inspection of the difference curve, interpretation of the different features.

10  Post-refinement calculations: Distances, angles and Bond-Valence sums
(programs: Bond_Str and GBond_Str). The programs Fourier and GFourier.
Visualisation of structures using FullProf Studio.

Practical session  Setting up an input control file for FullProf.
Automatic modes of refinement. Hints and tricks.
Using the simulated annealing method implemented in FullProf.
Training using example files distributed within the FullProf Suite.
Complete treatment of a case problem: solving and refining the crystal
structure of a perovskite-like material, using x-ray and neutron
diffraction data. The use of instrumental resolution function files.
Combined refinements. Multi-phase refinements.


29/01/2009
 (Special topic: Magnetic Structures I)

11  Magnetic structures. Description using the formalism of propagation
vectors. Symmetry analysis: Magnetic Space Group and Representation
theory.
The magnetic Bragg intensities: magnetic interaction vector and magnetic
structure factor. Polarised neutrons. Blume equations. Powder and
single-crystal magnetic diffraction. Domains. 3D polarimetry.

12  Magnetic structure determination using powder diffraction. Simulated
Annealing. Limitations of powder diffraction. Examples of magnetic
structure determination: commensurate and incommensurate structures.
Magnetic structure refinements. Sequential refinements.

Practical session  Complete examples of magnetic structure determination
and refinement using powder diffraction.
Setting-up of magnetic structure refinements for single crystal work.
Using WinPLOTR (under Windows) for visualising the sequential refinement
results.


30/01/2009
 (Special topic: Magnetic structures II)

13  Symmetry and magnetism. Magnetic space groups and representation
analysis (cont.). The use of the program BasIreps. Examples and issues.
Interpretation of magnetic structures in terms of exchange interactions.
Use of utility programs: Simbo, Enermag.

14  Refinement of single crystal data using FullProf. How to handle the
problem of domains. The use of DataRed for data reduction. Spin densities:
refinement of Flipping ratios using FullProf.

Practical session  Sequential refinements of magnetic structures.
Spin reorientations. Complete treatment of a case problem: solving and
refining the magnetic structure of a perovskite-like material.
Incommensurate magnetic structures. Single crystals.


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