PBE0 MULTIPLICITY 1 calculation

carlo antonio pignedoli c.pig... at gmail.com
Tue Jan 14 11:08:05 UTC 2014

Dear all,
 I am doing a PBE0 calculation for a periodic quasi 1D system (a graphene

I did restart the calculation from a converged antiferromagnetic PBE

The PBE0 calculation terminated with a unequal number of alpha and beta
orbitals thus violating (I guess) the MULTIPLICITY 1 of the input and of
the restart.
355 alpha and 349 beta while it should be  352 alpha and 352 beta
this can be seen checking   the added mos
declared at the end of the file: should have been 100 and 100 instead it is
97 102
and form the file with occupation numbers of the states (which I do not

I enclose the input file and the output, what is scaring is a sudden jump
of the energy at
the beginning of the SCF (from -980 to -1200 at step 24 of the scf) that
could be related to problems with the coulomb cutoff.

Does anybody have suggestions about what could be wrong?
Could it be that the cell size is too small for this particular system
(however it is big enough
to have a fair PBE description)?
(Basically I have 12 unit cells of a zig-zag graphene nanoribbon with at
least 20A of vacuum in the non periodic directions, the PBE UKS
calculationn produces the correct edge states but of course these states
are nearly metallic and have, in PBE a small gap)

Kind regards

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20140114/3c267ace/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: out
Type: application/octet-stream
Size: 88498 bytes
Desc: not available
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20140114/3c267ace/attachment.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: inp
Type: application/octet-stream
Size: 3401 bytes
Desc: not available
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20140114/3c267ace/attachment-0001.obj>

More information about the CP2K-user mailing list