SAPT is a collection of computer codes designed to implement the many-body (body = electron) version of Symmetry-Adapted Perturbation Theory for intermolecular interactions. This code has been extensively used in studies of intermolecular forces. For a description of SAPT see: B. Jeziorski, R. Moszynski, and K. Szalewicz “Perturbation Theory Approach to Intermolecular Potential Energy Surfaces of van der Waals Complexes”, Chem. Rev. 94, 1887-1930 (1994).
ESTEST (es-test) is a framework to facilitate the verification and comparison of Electronic Structure codes like Qbox, Quantum Espresso, Siesta, ABINIT, and The Exciting Code. The ESTEST framework consists of three components: automated input/output handling; translation to unified-representation (UR) XML format tools; rich web interface.
MOPAC (Molecular Orbital PACkage) is a semiempirical quantum chemistry program based on Dewar and Thiel's NDDO approximation. Available at this site are the open source version (OpenMOPAC) and information on the commerical version.
cclib is an open source library, written in Python, for parsing and interpreting the results of computational chemistry packages. The current version parses output files from ADF, GAMESS (US), GAMESS-UK, Gaussian, Jaguar, Molpro, ORCA and Firefly.
Molden is a package for displaying Molecular Density from the Ab Initio packages GAMESS-UK , GAMESS-US and GAUSSIAN and the Semi-Empirical packages Mopac/Ampac, it also supports a number of other programs via the Molden Format. Molden reads all the required information from the GAMESS / GAUSSIAN outputfile. Molden is capable of displaying Molecular Orbitals, the electron density and the Molecular minus Atomic density.
A page run by the center for computational studies of electronic structure and spectroscopy of open-shell and electronically excited species. Links to educational material on quantum chemistry, a forum, and free software are found here.
The Computational Chemistry Comparison and Benchmark Database (CCCBDB) contains links to experimental and computational thermochemical data for a selected set of gas-phase atoms and molecules as well as tools for comparing experimental and computational ideal-gas thermochemical properties.
The Quantum Chemistry Literature DataBase (QCLDB) is a database of those papers published after 1978 which treat ab initio calculations of atomic and molecular electronic structure. From about thirty core journals they are collected, surveyed, and given proper tags revealing the content and essence of the paper by the group of young Japanese quantum chemists. Those theoretical works even without reporting any computational results are also collected which are judged to have significant relevance to ab initio calculations, while no semi-empirical calculations are included. QCLDB is finally edited and copyrighted by Quantum Chemistry DataBase Group (QCDBG).
PyQuante is an open-source suite of programs for developing quantum chemistry methods. The program is written in the Python programming language, but has many "rate-determining" modules also written in C for speed.
COLUMBUS is a collection of programs for high-level ab initio molecular electronic structure calculations. The programs are designed primarily for extended multi-reference (MR) calculations on electronic ground and excited states of atoms and molecules.
A database containing many publicly available Gaussian basis sets for quantum chemistry calculations, including literature references. The basis sets can be displayed in input formats suitable for a number of quantum chemistry programs.