PyQuante is a free and open source suite of programs that will help you develop quantum chemistry methods. PyQuante is written in the Python programming language, but has many "rate-determining" modules also written in C for speed. The goal of PyQuante is not necessarily to provide a working quantum chemistry program (although it will hopefully do that), but rather to provide a well-engineered set of tools so that scientists can construct their own quantum chemistry programs without going through the tedium of having to write every low-level routine.
Features of PyQuante
- Hartree-Fock: Restriced closed-shell HF and unrestricted open-shell HF;
- DFT: LDA (SVWN, Xalpha) and GGA (BLYP) functionals;
- Optimized-effective potential DFT;
- Two electron integrals computed using Huzinaga, Rys, or Head-Gordon/Pople techniques; C and Python interfaces to all of these programs;
- MINDO/3 semiempirical energies and forces
- CI-Singles excited states
- DIIS convergence acceleration
- Second-order Moller-Plesset (MP2) perturbation theory.