# VASP

## Setting up VASP

In order to use VASP, you must be a part of the `vasp` group on Oscar. To check your groups, run the `groups` command in the terminal.

First, you must choose which VASP module to load. You can see the available modules using `module avail vasp`. You can load your preferred VASP module using `module load <module-name>`.

### Available Versions

* VASP 5.4.1
* VASP 5.4.4
* VASP 6.1.1

## Running VASP

Within a batch job, you should specify the number of MPI tasks as

```bash
mpirun -n <number-of-tasks> vasp_std
```

If you would like 40 cores for your calculation, you would include the following in your batch script:

```bash
# 2 nodes
#SBATCH -n 2
# 20 tasks per node
#SBATCH --ntasks-per-node=20

mpirun -n 2 vasp_std
```

{% hint style="info" %}
If you're not sure how many cores you should include in your calculation, refer to [Selecting the right amount of cores for a VASP calculation](https://www.nsc.liu.se/~pla/blog/2015/01/12/vasp-how-many-cores/)
{% endhint %}


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