Home
ARC - Automated Rate Calculator is a software written in Python for automating quantum electronic structure calculations and determination of thermoproperties and reaction rates.
ARC is currently in beta (under development), and features are constantly being added. For example, it performs quite well for thermoproperties determination, yet reaction rates haven't been implemented yet.
In it's current version, ARC is meant to be run on a computer that can SSH into server/s with ESS (electronic structure software). We do plan to eventually to make ARC compatible with running "locally" on a server.
ARC currently supports Gaussian, QChem, and Molpro, additional ESS support such as NWChem and Orca is planned.
Principally ARC takes 2D geometric representations of molecules (either xyz coordinates, SMILES, adjacency list, or RMG's Species / Molecule objects) and does the following:
- Generates numerous 3D conformers using RDKit and OpenBabel and rates them by energy using force fields.
- Optimizes the best conformers at a low level DFT
- Optimizes the lowest energy conformer at a high level DFT
- Calculates frequencies, single point energies and scans for rotors
- If a stable species has one or more imaginary frequencies ARC will perturb the geometry and search for a stable conformer. Alternatively, if a rotor scan shows that the initial geometry isn't the most stable conformation on the potential, ARC will change the respective dihedral angle and restart the jobs for the species.
- If any calculation fails ARC will apply its troubleshooting methods
- Calculate thermoproperties (enthalpy, entropy, heat capacity) using Arkane
- Determine thermoproperties using RMG's database and generate parity plots for reality checks.
Principally this GitHub repository should be cloned, and several packages including RMG must be installed.
See the Installation instructions
Currently the best way to run ARC is from a Jupyter notebook.
All the user should do is define the requires species / TSs, make the ARC object and execute it.
See the ARC Demo for example.
In addition to the running instructions, advanced features worth looking at are available.