PROGRAM SUMMARY
Title of program:
pwpaw
Catalogue identifier:
ADNP
Ref. in CPC:
135(2001)348
Distribution format: tar gzip file
Operating system: Unix
High speed store required:
100MK words
Number of lines in distributed program, including test data, etc:
885380
Keywords:
Solid state physics, Band structure, Electronic structure
calculations, Density functional calculation, Local density
approximation, Projector augmented wave method, PAW,
Calculational methods.
Programming language used: Fortran
Computer:
DEC Alpha ,
IBM SP2 .
Nature of problem:
The projector augmented wave (PAW) method, developed by Blochl, is a
very powerful tool for performing electronic structure calculations
in the framework of density functional theory, combining some of the
best features of pseudopotential and all-electron approaches. The pwpaw
program finds the one-electron eigenfunctions and eigenvalues for a
periodic system, and optionally optimizes or performs molecular dynamics
on the atomic positions within the unit cell.
Method of solution:
The program initializes the wavefunctions with a linear combination of
atomic orbitals (LCAO) or with a random number generator and determines
the eigenstates of the generalized eigenvalue problem by iterative
diagonalization. The atomic forces are calculated, using a modified
Feynman-Hellmann approach, from a knowledge of the converged
eigenstates.
Restrictions:
In this version of the code, only serial processing has been
implemented. In addition, of the many exchange-correlation functionals,
only the local density approximation (LDA) is currently available.
Also, relativistic and magnetic effects are not yet coded.
Typical running time:
Roughly 3-15 minutes/atom for each geometry on an SP2 computer.
Unusual features:
The program sequence is controlled by a keyword input file. A memory
management scheme is implemented which enables the user to tune the
program to make optimal use of available computer resources.
The library packages BLAS, LAPACK (available from
http://www.netlib.org), and FFTW (available from http://www.fftw.org)
are needed.