Elsevier Science Home
Computer Physics Communications Program Library
Full text online from Science Direct
Programs in Physics & Physical Chemistry
CPC Home

[Licence| Download | New Version Template] aefc_v2_0.tar.gz(1836 Kbytes)
Manuscript Title: Efficient self-consistency for magnetic tight binding
Authors: Preetma Soin, A. P. Horsfield, D. Nguyen-Manh
Program title: PLATO
Catalogue identifier: AEFC_v2_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 182(2011)1350
Programming language: C and PERL.
Computer: Apple Macintosh, PC, Unix machines.
Operating system: Unix, Linux, Mac OS X, Windows XP.
Has the code been vectorised or parallelized?: Yes. Up to 256 processors tested.
RAM: Up to 2 Gbytes per processor
Keywords: Atomic orbitals, density functional theory, tight binding.
PACS: 75.50.Bb, 75.10.-b, 71.55.Ak, 71.15.Dx.
Classification: 7.3.

External routines: LAPACK, BLAS and optionally ScaLAPACK, BLACS, PBLAS, FFTW

Does the new version supersede the previous version?: Yes

Nature of problem:
Achieving charge and spin self-consistency in magnetic tight binding can be very difficult. Our existing schemes failed altogether, or were very slow.

Solution method:
A new scheme for achieving self consistency in orthogonal tight binding has been introduced that explicitly evaluates the first and second derivatives of the energy with respect to input charge and spin, and then uses these to search for stationary values of the energy.

Reasons for new version:
Bug fixes and new functionality.

Summary of revisions:
New charge and spin mixing scheme for orthogonal tight binding. Numerous small bug fixes.

The new mixing scheme scales poorly with system size. In particular the memory usage scales as number of atoms to the power 4. It is restricted to systems with about 200 atoms or less.

Running time:
Test cases will run in a few minutes, large calculations may run for several days.