# Gaussian

## Setting Up Gaussian

In order to use Gaussian on Oscar, you must be a part of the `ccv-g09` group. To check your groups, run the `groups` command in the terminal.

You must first choose a Gaussian module to load. To see available Gaussian modules, run `module avail gauss`. You can load a Gaussian module using the command `module load <module-name>`.

### Available Versions

* Gaussian 9 (g09)
* Gaussian 16 (g16)

NOTE: There are three versions of `g09`, you can load any one of those, but the newer version `g16` is preferred now. If using `g09` just replace `g16` below with `g09`.

## Running Gaussian

Gaussian can be run either interactively or within a batch script using one of two command styles:

* `g16 job-name`
* `g16 <input-file >output-file`

In the first form, the program reads input from `job-name.gjf` and writes its output to `job-name.log`. When no job-name has been specified, the program will read from standard input and write to standard output

Given a valid .gjf file (we'll call it `test-file.gjf`), we can use the following simple batch script to run Gaussian:

### g16-test.sh

```bash
#!/bin/sh
# Job name
#SBATCH -J g16-test

# One task/node
#SBATCH -n 1

# Eight CPUs per task
#SBATCH -c 8

# batch partition
#SBATCH -p batch

# Run the command
g16 test-file.gjf
```

Then queue the script using

```bash
sbatch g16-test.sh
```

Once the job has been completed, you should have a `g16-test.out`, a `g16-test.err`, and a `test-file.out`.


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.ccv.brown.edu/oscar/software/gaussian.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.