Time-stamp: <2000/03/11 21:39:23 bruce>
-------------------------------------------------------------------
      Copyright (c) 2000 Bruce Ravel
      Permission is granted to copy, distribute and/or modify this
      document under the terms of the GNU Free Documentation License,
      Version 1.0 or any later version published by the Free Software
      Foundation; with the Invariant Sections being "EXAFS Analysis
      Using FEFF and FEFFIT, Part 1: Presentation", "EXAFS Analysis
      Using FEFF and FEFFIT, Part 2: Commentary", and all related
      analysis examples, with no Front-Cover Texts, and with no
      Back-Cover Texts.  A copy of the license is included in the
      section entitled "GNU Free Documentation License".


This file (and all files associated with `EXAFS Analysis Using FEFF
and FEFFIT') are free documentation; you can redistribute it and/or
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published by the Free Software Foundation; either version 1, or (at
your option) any later version.

You should have received a copy of the GNU Free Documentation License
along with `EXAFS Analysis Using FEFF and FEFFIT'; see the file
COPYING.  If not, write to the Free Software Foundation, 675
Massachusettes Ave, Cambridge, MA 02139, USA.

Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.

Permission is granted to copy and distribute modified versions of this
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This directory contains various examples and exercises to go along
with `EXAFS Analysis Using FEFF and FEFFIT'.  Each subdirectory is
devoted to a sample material and contains data files and input files.
The input files are by no means complete, but in each case provide
enough illustration to get you started in analyzing the data.

Each subdirectory has feffit input files and three subdirectories.
The `data/' subdirectory contains data files -- always mu(E) and
sometimes chi(k).  The `feff/' directory contains Atoms input files if
the matrial is crystalline and Feff input files if not.  The `fits/'
subdirectory is usually empty, but the Feffit input files are set up
to write their output to those spaces.

The examples provided are:

Cu -- copper metal

  This is the best place to start learning Feff and Feffit.  The
  structure is very simple and it is easy to obtain a good fit.

GaN -- hexagonal Gallium Nitride

  This is an example of a polar material.  Data is provided with the
  incident beam polarized along and perpendicular to the c axis.

EuTiO3 -- cubic Europium Titanate

  This is a simple structure and data is provided for the Ti K edge
  and the Eu L3 edge at various temperatures.  This is a fairly simple
  example of multiple data set fits.  You can try corefining the two
  edge and the various temperatures.

PbTiO3 -- tetragonal Lead Titanate

  This is a much more complex structure.  It illustrates well Feffit's
  sophisticated model building capabilities.  The Feffit input files
  demonstrate using math expressions to express all path lengths in
  terms of crystallographic parameters.  It also demonstrates a method
  for considering change multiple scattering bond angle in terms of
  the fitting parameters.  See Bruce Ravel's doctoral dissertation,
  Phys. Rev. B50, pp 13168-13180 (1995), and Ferroelectrics v. 164,
  pp. 256--277 (1995).

AgBrCl

  This is a simple binary phase mixture (approximately 50-50) of two
  alkali halides with data measured at the Ag K edge.  This is an
  introduction to the consideration of dopants and mixed phase
  materials in feffit.