How to build PAW atomic data for Abinit using USPP generator

Current version of USpp2Abinit :v2.4.0

Available for Abinit v5.4.3+
See this note for use with previous versions of Abinit

 

To obtain PAW atomic data for Abinit we proceed as follows:
    - We patch D. Vanderbilt's USPP package in order to make it generate PAW atomic data in Abinit's format (in addition to ultrasoft pseudopotentials).

    - "Patched" USPP is directly useable to produce PAW atomic data from normal USPP input files.

Many thanks to D. Vanderbilt for having given us the opportunity to use USPP package.

1. What you need:

We suppose for the following that the reader is familiar with the use of USPP package.
If not, first take at look at the complete user's guide written for it.
2. Preliminary steps: patching USPP

3. Generating a  PAW "pseudopotential file" for Abinit:

Go into /uspp-xyz/Work directory; browse down sub-directories, selecting chemical specie and density functional (LDA, GGA).
Type
make clean; make
If you encounter some error during execution, look for an error message in the ??_ae.out or ??_ps.out file; if the error message is not explicit enough, look at
Doc/TUTORIAL (most of the problems are referenced inside).

 

Real Space Optimisation improve the development of non-local projectors by "smoothing" their development over large G vectors (introducing a "controlled" error). It has been proposed by King-Smith and al. (see [4] below).
The scheme is governed by 3 parameters: Gmax (=2*Ecut**2), Gamma and Wl ; the user has to give these parameters in uspp2abinit.dat file.
The efficiency of Real Space Optimization strongly depends on the non-local projectors produced by USPP (it can be sometimes unuseful); only experienced users should use it... 

 

4. Additional remarks:

5. References:

[1]  Soft Self-Consistent Pseudopotentials in a Generalized Eigenvalue Formalism,
D. Vanderbilt, Phys. Rev. B 41  (Rapid Communications), 7892 (1990)

[2] Implementation of Ultra-Soft Pseudopotentials in Ab-initio Molecular Dynamics,
K. Laasonen, R. Car, C. Lee, D. Vasnderbilt, Phys. Rev. B 43 (Rapid Communications), 6796 (1991)

[3] From ultrasoft pseudopotentials to the projector augmented-wave method,
G. Kresse, D. Joubert, Phys. Rev. B 59, 1758 (1999)

[4]  Real-space implementation of nonlocal pseudopotentials for 1st-principle total-energy calculations,
R.D. King-Smith, M.C. Payne, J.S. Lin, Phys. Rev. B 44, 13063 (1991)

[5]  Implementation of the projector augmented-wave method in the ABINIT code: Application to the study of iron under pressure,
M. Torrent, F. Jollet, F. Bottin, G. Zerah and X. Gonze, Comput. Mater. Sci. 42, 337 (2008)


6. Contacts:
In case of problem or questions contact the authors.

Marc Torrent
François Jollet
Département de Physique Théorique et Appliquée
CEA, DAM, DIF
F-91127 Arpajon
France

Last modification : may 11th 2010