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The ShARC HPC cluster was decommissioned on the 30th of November 2023 at 17:00. It is no longer possible for users to access that cluster.


An ab initio, DFT and semiempirical SCF-MO package. The program ORCA is a modern electronic structure program package written by F. Neese, with contributions from many current and former coworkers and several collaborating groups. The binaries of ORCA are available free of charge for academic users for a variety of platforms.


ORCA 4.0.1 can be activated using the module file:

module load apps/orca/4.0.1/binary

The ORCA 4.0.1 executable is orca. All the ORCA 4.0.1 executables are in /usr/local/packages/apps/orca/4.0.1/binary/orca_4_0_1_linux_x86-64_openmpi202.

Batch jobs

Users are encouraged to write their own batch submission scripts. The following is an example batch submission script,, to run orca and which is submitted to the queue by typing qsub

#$ -cwd
#$ -l h_rt=00:30:00
#$ -l rmem=2G

module load apps/orca/4.0.1/binary

orca my_input.inp > my_input.out

The script requests a serial job with a runtime of 30 mins and 2G of real memory. The ORCA 4.0.1 input file is my_input.inp.

Installation notes

ORCA 4.0.1 was installed as a binary installation using the script; the module file is binary.

The ORCA 4.0.1 installation was tested by running a batch job using the batch script, above, with the text, below, in an ORCA input file.

# My first ORCA calculation :-)
* xyz 0 1
C 0 0 0
O 0 0 1.13