pyEsm is a personal attempt at building a quantum chemistry software package in python. The focus for this project was therefore more so about learning and not so much about building the fastest & most optimized quantum chemistry package.
Installation is recommended through Conda:
- Make sure you have a working installation of openbabel on your computer
- Git clone the pyEsm project
- Inside pyEsm, type: 'conda env create -f environment.yml'
- next: 'conda activate pyEsmFinal'
- run 'pytest' in the terminal, to see if the environment creation was succesfull
- run: 'python backend.py' to start the Flask server
Energy calculations can be performed on Molecule objects, which can be initiated using a SMILES string.
- (HF) Restricted Hartree Fock
- (MP2) Moller-Presset 2nd order perturbation theory
- (CCSD) Coupled Cluster single-double excitations
- (DFT) Density Functional theory using a LSDA functional
The basis-set data is fetched via the basis set exchange API: https://www.basissetexchange.org/. Most available basis-sets that can be found there will also work in pyEsm.
The McMurchie-Davidson scheme was used for evaluating the gaussian integrals, largely based on Chapter 9 of the book 'Molecular Electronic-Structure Theory' by Helgaker, Jorgensen & Olsen.