5
$\begingroup$

There is job.sh script in a lot of official VASP examples, for example: Graphite MBD binding energy. it is used to help submit job on supercomputer
But in the script, it usually uses vaspcmd, which I am not sure what it is, I checked the vasp wiki and vasp help document, there is not explanation about it.
My question is:
What is vaspcmd?


#
# To run VASP this script calls $vasp_std
# (or posibly $vasp_gam and/or $vasp_ncl).
# These variables can be defined by sourcing vaspcmd
. vaspcmd 2> /dev/null

#
# When vaspcmd is not available and $vasp_std,
# $vasp_gam, and/or $vasp_ncl are not set as environment
# variables, you can specify them here
[ -z "`echo $vasp_std`" ] && vasp_std="mpirun -np 8 /path-to-your-vasp/vasp_std"
[ -z "`echo $vasp_gam`" ] && vasp_gam="mpirun -np 8 /path-to-your-vasp/vasp_gam"
[ -z "`echo $vasp_ncl`" ] && vasp_ncl="mpirun -np 8 /path-to-your-vasp/vasp_ncl"

#
# The real work starts here
#

# Here the work starts
rm results.dat

drct=$(pwd)

for i in graphene graphite
do
  cd $drct/$i
  $vasp_std
done

cd $drct

# obtain total energy for graphite 
en2=$(grep "free  ene" graphite/OUTCAR |tail -1|awk '{print $5}') 

# obtain total energy for graphene
en1=$(grep "free  ene" graphene/OUTCAR |tail -1|awk '{print $5}')

# compute interlayer binding energy (eV/atom)
deltaE=$(echo print $en2/4 - $en1/2 |python)

echo "Binding energy (eV/atom): " $deltaE >results.dat
Improve this question
$\endgroup$
2
  • $\begingroup$ I don't use VASP, so someone else will probably be able to answer this better, but it seems like vaspcmd is a variable that some scripts define that just stores the path/settings for the VASP executable. As far as I can tell, this is not a part of VASP and is something you would have to define/fill-in yourself similar to /path-to-your-vasp/vasp_std in the example code. $\endgroup$
    – Tyberius ♦
    Jan 6, 2022 at 17:56
  • 1
    $\begingroup$ It's a file containing environment variable definitions and (potentially) shell functions. I don't know much about VASP, but you can tell that must be what it is because it is included with the "source" command -- although this script uses its alternative "." which makes it extra confusing if you haven't seen it before. It must define the variables vasp_std, vasp_gam and vasp_ncl at least, because (a) the comment says so; and (b) the rest of the script uses them! You could easily write your own, but it might be worth looking in the VASP source tree to see if there's a sample provided. $\endgroup$
    – Phil Hasnip
    Jan 6, 2022 at 22:54

1 Answer 1

Reset to default
4
$\begingroup$ 
#
# To run VASP this script calls $vasp_std
# (or posibly $vasp_gam and/or $vasp_ncl).
# These variables can be defined by sourcing vaspcmd
. vaspcmd 2> /dev/null

As mentioned in the comments, the answer is actually in your question. vaspcmd is just any script you provide that defines the $vasp_std, $vasp_gam and $vasp_ncl variables which give the full path to the executables. You must write this script, it is not provided since it depends on the installation location.

Improve this answer
$\endgroup$

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .