ORCA requires each user to register, (see https://orcaforum.kofo.mpg.de), and send the confirmation mail to email@example.com. After the confirmation mail has been received by firstname.lastname@example.org the user will be added to the ORCA group in SUPR (supr.snic.se) and access to the ORCA installation at HPC2N will be granted.
ORCA is a tool for quantum chemistry with specific emphasis on spectroscopic properties of open-shell molecules.
ORCA is a flexible, efficient and easy-to-use general purpose tool for quantum chemistry with specific emphasis on spectroscopic properties of open-shell molecules. It features a wide variety of standard quantum chemical methods ranging from semiempirical methods to DFT to single- and multireference correlated ab initio methods. It can also treat environmental and relativistic effects.
At HPC2N ORCA is available to users that have been verified to have registered for a license at https://orcaforum.kofo.mpg.de
The binaries for ORCA is available through the module system.
module spider ORCA
to see which versions are available.
ORCA requires that one specifies the full path to the binary when starting, so one must always use
when starting it.
Submit file example
Regardless of running a serial job or a parallel (MPI) job, the binary to use is "orca". It will internally start the sub-parts and if "nprocs" is > 1 in the input file it will use MPI versions and will handle the MPI startup. So the only submit file you need is:
#!/bin/bash #SBATCH -A SNICXXXX-YY-ZZ #SBATCH -n 8 #SBATCH -t 01:00:00 ml purge > /dev/null 2>&1 ml foss/2019a ml ORCA/4.2.0 $EBROOTORCA/orca inputfile.inp
Make sure that the value to "-n" above matches the "nprocs" value in the input file.