Introduction

The General Atomic and Molecular Electronic Structure System (GAMESS) is a program for ab initio quantum chemistry. GAMESS can compute SCF wavefunctions ranging from RHF, ROHF, UHF, GVB, and MCSCF. Correlation corrections to these SCF wave functions include Configuration Interaction, second order perturbation Theory, and Coupled-Cluster approaches, as well as the Density Functional Theory approximation. Excited states can be computed by CI, EOM, or TD-DFT procedures. Nuclear gradients are available for automatic geometry optimization, transition state searches, or reaction path following. Computation of the energy hessian permits prediction of vibrational frequencies, with IR or Raman intensities. Solvent effects may be modeled by the discrete Effective Fragment potentials, or continuum models such as the Polarizable Continuum Model. Numerous relativistic computations are available, including infinite order two component scalar relativity corrections, with various spin-orbit coupling options. The Fragment Molecular Orbital method permits use of many of these sophisticated treatments on very large systems, by dividing the computation into small fragments. Nuclear wavefunctions can also be computed in VSCF or with explicit treatment of nuclear orbitals by the NEO code.

For more information, visit the GAMESS official website.

Programming language: C/Fortran 90

Brief description: GAMESS can compute SCF wavefunctions ranging from RHF, ROHF, UHF, GVB, and MCSCF.

Open source license: GPL 3.0