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Programs
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Indexing Programs
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Library
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What is FullProf?
The FullProf program has been mainly developed
for Rietveld analysis (structure profile refinement) of neutron (constant
wavelength, time of flight, nuclear and magnetic scattering) or X-ray powder
diffraction data collected at constant or variable step in scattering angle
2theta. The program can be also used as a Profile Matching (or pattern decomposition
using Le Bail method) tool, without the knowledge of the structure. Single crystal
refinement can also be performed alone or in combination with powder data. Time of flight
(TOF) neutron data analysis is also available. Energy dispersive X-ray data
can also be treated but only for profile matching.
Features:
- X-ray diffraction data: laboratory
and synchrotron sources
- X-ray diffraction data: laboratory and synchrotron
sources
- One or two
wavelengths (eventually with different profile parameters)
- Scattering variables: 2theta (in degrees), TOF
(in microseconds), energy (in KeV)
- Background: fixed, refinable points or polynomial
coefficients, Fourier filtering
- Choice of peak shape for each phase: Gaussian,
Lorentzian, modified Lorentzian, pseudo-Voigt, Pearson-VII, Thompson-Cox-Hastings
(TCH) pseudo-Voigt, numerical, split pseudo-Voigt, convolution of a double
exponential with a TCH pseudo-Voigt for TOF
- Multi-phase (up to 16 phases)
- Preferred orientation: two functions available
- Absorption correction for different geometries.
Micro-absorption for Bragg-Brentano set-up
- Choice between three weighting scheme: standard
least-square, maximum likelihood and unit weights
- Choice between automatic generation of hkl
and/or symmetry operators and file given by user
- Magnetic structure refinement (crystallographic
and spherical representation of the magnetic moment). Two methods: describing
the magnetic structure in the magnetic unit cell or making use of the propagation
vectors using the crystallographic unit cell. This second method is necessary
for incommensurate magnetic structures
- Automatic generation of reflections for an incommensurate
structure with up to 24 propagation vectors. Refinement of propagation vectors
components in reciprocal lattice units
- hkl-dependence of FWHM for strain and size effects
- hkl-dependence of the position shifts of Bragg
reflections for special kinds of defects
- Profile Matching: the full profile can be adjusted
without prior knowledge of the structure (needs only good starting cell parameters
and profile parameters)
- Quantitative analysis withour need of structure
factor calculations
- Chemical (distances and angles) and magnetic
(magnetic moments) slack constraints. They can be generated automatically
by the program
- The instrumental resolution function (Voigt
function) may be supplied in a file. A microstructural analysis is then performed
- Form factor refinement of complex objects (plastic
crystals)
- Structural or magnetic model could be supplied
by an external subroutine for special purposes (rigid bodies TLS is the default,
polymers, small angle scattering of amphifilic crystals, description of incommensurate
structure in real direct space, etc)
- Single crystal data or integrated intensities
can be used as observations (alone or in combination with a powder profile)
- Neutron (or X-ray) powder patterns can be mixed
with integrated intensities of X-ray (or neutron) for single crystal or powder
data
- Full multi-pattern capabilities. The user may
mix several powder diffraction patterns (eventually heterogeneous: X-rays,
TOF neutrons, etc.) with total control of the weighting scheme
- Montecarlo/Simulated Annealing algorithms have
been introduced to search the starting parameters of a structural problem
using integrated intensity data
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