ORCA

ORCA

Introduction

The program ORCA is a modern electronic structure program package that is able to carry out geometry optimizations and to predict a large number of spectroscopic parameters at different levels of theory. Besides the use of Hartee Fock theory, density functional theory (DFT) and semiempirical methods, high level ab initio quantum chemical methods, based on the configuration interaction and coupled cluster methods, are included into ORCA to an increasing degree.

For more details please refer the offical home of ORCA where you can also find a thorough documentation on using the program. Note that ORCA is free of charge for non-commercial use and by using ORCA on the cluster you are accepting the ORCA license. In particular, any scientific work using ORCA should at least cite

F. Neese: The ORCA program system (WIREs Comput Mol Sci 2012, 2: 73-78)

as well as other related works as apropriate.

Below, a short introduction to using ORCA on the cluster is given.

Using ORCA on the Cluster

The first thing that you need to do is to load the ORCA module using the command

module load orca

This will load the latest version of ORCA installed (currently, 3.0.3). More specifically, it adds the path of the ORCA executables to your environment.

Next, you will need to prepare a job script which could look as follows:

to be added

Once the job script is available and your input file is ready, a job can be submitted as usual with the command:

qsub orca.sge