Summary
Source: Download page on orca forum - requires registration
Documentation: https://orcaforum.kofo.mpg.de/index.php
License: see below
Path: /software/orca
ORCA is an ab initio quantum chemistry program package that contains modern electronic structure methods including density functional theory, many-body perturbation, coupled cluster, multireference methods, and semi-empirical quantum chemistry methods. Its main field of application is larger molecules, transition metal complexes, and their spectroscopic properties.More information about Orca can be found on the orca forum.
Installations on Maxwell
Various versions are installed on the maxwell cluster. To set the environment use the module command
module load maxwell module load orca # will select the most recent version module load orca/5.0.3 # will select a specific version xwhich orca # will list available orca versions and corresponding module commands
When using orca you implicitly agree to the license and terms of use, for ORCA and a number of Third Party products included into ORCA.
Orca License
The EULA license for orca can be obtained from the orca forum. A current copy of the EULA license and Third Party License can be found under /software/orca/license/. Please read prior to using ORCA!
Particularly important:
5. OBLIGATIONS OF LICENSEE:
LICENSEE shall immediately notify SGK if LICENSEE or ACADEMIA LICENSEE is working for, is filing a patent as a result of LICENSEE’s use of SOFTWARE.
MPI and SGK are entitled to use the information in the patent application for marketing purposes and to publish it for this specific purpose.
If results obtained with SOFTWARE are published in the scientific literature, LICENSEE shall reference the SOFTWARE as:
“F. Neese: Software update: the ORCA program system, version 4.0 (WIREs Comput Mol Sci 2018, 8:e1327. doi: 10.1002/wcms.1327)”. Using specific methods included in SOFTWARE may require citing additional articles, as described in the manual. LICENSEE agrees to honor the request to cite additional papers as appropriate.
Orca sample batch script
the Maxwell nodes are rather well equipped with memory, so it might be favorable to use memory for orca rather than beegfs for temporary files. Sample batch script:
#!/bin/bash
#SBATCH --partition=all
#SBATCH --time=0-12:00:00
#SBATCH --job-name=cluster44
#SBATCH --nodes=4
#SBATCH --constraint='[7402|Gold-6240|Gold-6140|75F3]'
unset LD_PRELOAD
# make sure current state gets saved even when jobs get terminated (timeout, preemption)
term_handler()
{
rm -f $tdir/*.tmp
cp -v $tdir/*.* $rdir/
}
trap 'term_handler' TERM
# general setup. orca module includes openmpi setup
source /etc/profile.d/modules.sh
module purge
module load maxwell orca/4.2.1
# N=number of physical cores, np=total number of physical cores
# using constraints, all nodes in the job should see the same number of course
N=$(( $(nproc) / 2 ))
np=$(( $SLURM_NNODES * $N ))
# arbitrary folder to store results.
rdir=$PWD/cluster44
mkdir -p $rdir
# temporary files directory in memory. working dir for orca
tdir=/dev/shm/$USER
srun mkdir -p $tdir
# copy all input files to working dir and go there
cp cluster44.xyz.inp $tdir/
cd $tdir
# set total number of cores in input file
# note: this will only work if the setup looks like this (without leading #!)
#%pal
#nprocs 1
#end
perl -pi -e "s|^nprocs.*|nprocs $np|" cluster44.xyz.inp
# run orca
`which orca` cluster44.xyz.inp "-N $N -mca mpi_cuda_support 0 -mca pml ucx -mca btl_tcp_if_include ib0 --prefix ${MPI_HOME} -wdir $tdir" > $rdir/cluster44.out
# invoke term handler to copy files to $rdir
term_handler