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[Licence| Download | New Version Template] adqx_v1_0.tar.gz(935 Kbytes)
Manuscript Title: octopus: a first-principles tool for excited electron-ion dynamics.
Authors: M.A.L. Marques, A. Castro, G.F. Bertsch, A. Rubio
Program title: octopus
Catalogue identifier: ADQX_v1_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 151(2003)60
Programming language: Fortran, C, bison, sh.
Computer: IBM SP3.
Operating system: GNU/Linux, AIX, Tru64 Unix, Irix.
RAM: 50M words
Word size: 32
Keywords: Electronic structure, Linear response, Non-linear response, Non-adiabatic dynamics, Density-functional theory, Time-dependent density-functional theory, Local-density approximation, Generalized-gradient approximation, Real-space methods, Solid state physics, Band structure, Other.
Classification: 7.3, 7.7.

Nature of problem:
Interaction of quantum finite systems with classical electromagnetic fields. The electronic degrees of freedom are described within the Kohn-Sham form of the time-dependent density functional theory, while nuclei are treated as classical point particles.

Solution method:
The electronic wave-functions are discretized in real space using an uniform mesh, and are propagated in real time using nearly unitary propagation schemes. Pseudopotentials are normally used to describe the electron-ion interaction, although model interactions can also be employed. The electromagnetic fields are treated classically either in the length or in the velocity gauge.

The present version only handles finite systems and classical nuclei. In the near future the code will handle periodic structures.

Unusual features:
The program can be run in either one or three dimensions (we plan to support two dimensions and several categories of periodical systems in future versions). octopus makes use of a very sophisticated, but user-friendly input system.

Additional comments:
Libraries required:
  • BLAS (http://www.netlib.org/blas/),
  • LAPACK (http://www.netlib.org/lapack/),
  • FFTW (http://www.fftw.org/),
  • GSL (http://www.gnu.org/software/gsl/),
  • MPI (http://www-unix.mcs.anl.gov/mpi/).
All of these are available under open-source licences.
The code was parallelized with MPI.

Running time:
For the benzene example (section 7.1), the ground-state calculation took around 15 minutes (in a single processor), while each of the time-evolutions took around 2 days (using 8 processors). These numbers refer to an IBM SP3.