
Planning

This document describes a wish list for the ABINIT development,
more than a planning !
Since new features (to be coded) have been added very often, and
on the contrary features
that were coded have been removed, this file is changed very frequently.

Copyright (C) 1996-2009 ABINIT group (XG,DCA)
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 .

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1. Guidelines for establishing the planning
*******************************************

The classification of the work to be done is based on the following :

A. work needed to ease further developments,
     or needed for testing the code (language standard, test suites ...)
B. work needed to facilitate the use of the code
        (help files, better I/O files, pre- and post-processing)
C. work needed to increase the capabilities of the code (ground-state)
D. work needed to increase the capabilities of the code (response functions)
E. work needed to increase the capabilities of the code (excited states)
F. work needed to increase the speed of the code
G. work needed to improve utilities (cut3d, mrgddb, anaddb ...)

Note :
- major works are NOT distinguished from minor works
- of course, if somebody volunteer to implement a feature not listed
    the planning will be modified without problem !

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A. Development and testing
----------------------------

A.4 Self-documentation project : add a layer between sources and bibliography (MM...)
A.6 Examine how to use Python in the context of ABINIT (GZ)
A.7 Develop more datatypes, and the corresponding documentation.


B. Use of the code
--------------------

B.1 Complete bibliography file
B.3 Provide core-hole pseudopotentials for the most used
        elements in the periodic table
B.4 Provide advice on cut-off energy for all existing pseudopotentials.
        Set up a protocol for that purpose.
B.5 Improve the classification of messages (may be
        introduce a third class in addition to WARNING and COMMENT).
        For the time being, some
        WARNING messages should be only COMMENTS.
B.6 Improve tools for constructing phonon densities of states


C. Capabilities of the code (GroundState)
-----------------------------------------

C.1 Conjugate-gradient algorithm for the relaxation of ions
C.2 Allow to use the SCF preconditioner if spin-polarized and/or
        if a metal (some possibilities are not allowed yet)
        Optimize dieltcel.f routine, use inversion routine Lapack
        and unsymmetric eigenvalue solver
C.3 Allow a more general treatment of non-linear XC core correction.
        Also, mkcore should be used on finer grid. GGA with finer grid.
C.4 Exact exchange for molecule and solids
C.5 Optimized effective potentials
C.7 Complete the available options for FFTs
C.8 Might code another method for handling a metal.
C.9 Allow for the computation of properties at the nucleus site,
      thanks to the PAW method
C.11 Treat Hartree energy using Jarvis, White, Godby and Payne
     technique
C.13 Search for transition states
C.15 Hyperdynamics (see work by Voter)
C.17 Layer of dipoles in the vacuum, for polar surfaces,
       with the corresponding energy correction (FabioFinocchi+Francois).
C.18 Car-Parrinello type dynamics
C.21 (Improve) Frequency-dependent conductivity thanks to the Kubo-Greenwood
      formula (already coded by VRecoules)
C.23 Test and improve use of non-collinear magnetism


D. Capabilities of the code (Response Functions)
------------------------------------------------

D.2 Optimize Response functions with GGA
D.3 Remove other constraints placed upon response-function calculations.
D.5 Responses with respect to alchemical perturbations
D.6 Time-dependent responses using the linear-response part of the code
D.7 More 2n+1 theorem
D.9 Implement stationary formulation of mixed derivatives.
D.10 Better use of symmetries in RF.


E. Capabilities of the code (Excited states)
--------------------------------------------

E.1 Make GW technique more robust, and treat symmetries correctly
E.2 Bethe-Salpeter equation



F. Speed of the code, memory usage.
-----------------------------------

F.1 Optimize parallelisation of ground state on the bands
F.2 Treatment of non-local potentials in real space
F.5 Improve the approximate atomic density available
        for every pseudopotential. Provide a better starting
        point for response functions.
F.6 Improve preconditioning of SCF cycle, especially provide
        better default or expert system (for both ground state
        and response function)
F.7 Precondition geometry search. Use previous work by GMR.
F.9 Improved wf storage format (istwfk/=1) for RF and spin-orbit


G. Utilities
------------

G.2 Link to the Wannier function code by Marzari
G.4 Recode some parts of anaddb

