
This directory, physics, contains tests which 
are rather long, but close to convergence, so that
their results can be compared with experimental results.

Copyright (C) 1999-2009 ABINIT group (XG)
This file is distributed under the terms of the
GNU General Public License, see ~abinit/COPYING
or http://www.gnu.org/copyleft/gpl.txt .
For the initials of contributors, see ~abinit/doc/developers/contributors.txt .

Tests 1 to 3 are related to the computation of the phonon
 band structure of Niobium.


To run these tests, do the following:

0. Be sure that the perl script "run-standard-tests", in the main directory,
   has been generated from the primitive file "run-standard-tests.pl",
   thanks to the command "make perl"
   issued in ~abinit (see the installation notes on the Web).

1. Submit the "run-standard-tests" script, specifying a machine, and
   the keyword "physics" (for Tests_physics) and either
   the index of a test case, i.e.
   (run-standard-tests name_of_machine physics 01) >& log_file
   or a whole range of test cases (two indices), i.e.
   (run-standard-tests name_of_machine physics 01 02) >& log_file
   or, if you want to run all the test cases of this directory
   (run-standard-tests name_of_machine physics) >& log_file
   This will send stdout and stderr to log_file.
   The script 'run-standard-tests', will create a subdirectory of ~abinit/tests/physics,
   with the name_of_machine and the
   date, where all the results will be placed.

2. In that directory, you will find for each test case that you have
   run, a log file (with the name of the test case), an output
   file, but also a 'diff.xxx' file, automatically created by making
   a 'diff' with respect to the "Refs" subdirectory output files.
   It contains output files from a recent version of the ABINIT code.
   There may be large differences in timing but there should only
   be minor differences in the output of physical quantities.

3. There is also a global report file, generated by the use of the
   fldiff script. Its name is fldiff.report . See the last
   version of the  ~abinit/doc/install_notes/install** file
   in the Infos directory for information about the use of this file.
   This file is the most convenient for a quick look at the correctness
   of results. When the results are not correct, one has often to
   rely on the 'diff.xxx' file to understand what was going wrong.


**********

Test cases:

  1. BCC Niobium (1 atoms per unit cell),
     using a FHI pseudopotential, within LDA.
     Fixed cell dimensions.
     Compute the dynamical matrices at 14 different wavevectors,
     corresponding to a 8x8x8 Monkhorst-Pack grid.
     Also, the sampling of the electronic wavevectors
     corresponds to a 8x8x8 Monkhorst-Pack grid.
     ABINITv3.1 : take 18 hours on a PIII at 450 MHz .
     
  2. Merge the different DDB produced in run 1.

  3. Analyse the complete DDB produced in run 2.
     Compute the phonon band structure along selected
     lines : Gamma-(x00)-H-(xxx)-Gamma-(xx0)-N

