The ABINIT Users Mailing List ( CLOSED )

[Josef Zwanziger <jzwanzig@dal.ca>]

Dear Colleagues,

In the very useful part 6 of the elastic constants tutorial, where a metal is
treated, it is pointed out that it is necessary to use tolwfr as the
convergence parameter to ensure that the empty bands are also converged (as
opposed to using tolvrs, for example). The suggested procedure is 1) GS run
with tolvrs, followed by 2) non-self-consistent run with tolwfr, using the
density from 1) as input, to generate highly converged wave functions. 
However,
the tutorial file uses iscf 5 throughout, thus, a self-consistent calculation
is used also in the tolwfr part. So, what's the best approach? I'm assuming
that the point of the initial tolvrs scf calculation is simply to speed the
second, highly converged calculation, since the output of the first 
calculation
is not used anywhere else. Should the general approach actually be something
like:

1) iscf 5, tolvrs 1.0D-18, prtden 1

2) iscf -2, tolwfr 1.0D-22, getden 1, prtwf 1

3) iscf 5, tolvrs 1.0D-12, rfphon 1, getwfk 2

thanks for your help,

Joe Zwanziger