[DFTB-Plus-User] Band structure calculations for pentacene (2x2x2) supercell

[Bálint Aradi]

Dear Mahesh,

> This large interface has 4032 atoms and please let me know whether it is memory problem of our cluster or not.
> Or is there any alternative way to overcome such problems in DFTB+?

 It is quite likely that your cluster does not have enough memory to
handle it. The unpacked dense Hamiltonian requires in your case ca. 10
Gb of memory, the overlap the same. So, the computer you use should have
at least 25 GB of memory or more (four thousand atoms are quite a lot).

 Currently, there is no way to overcome this problem (apart of using a
cluster with more memory or calculating smaller systems). I am now
working on the MPI parallelized version of the code. That will enable
you to distribute the memory requirements among many nodes, so that the
memory requirement on one node would be moderate. When I have a working
version (hopefully around February), it will be available for testing
purposes (we'll announce it via this list).

  Best regards,

  Bálint

-- 
Dr. Bálint Aradi
Bremen Center for Computational Materials Science, University of Bremen
http://www.bccms.uni-bremen.de/cms/people/b_aradi/


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