GAMESS

The General Atomic and Molecular Electronic Structure System (GAMESS) is a general ab initio quantum chemistry package. Briefly, GAMESS can compute wavefunctions ranging from RHF, ROHF, UHF, GVB, and MCSCF, with CI and MP2 energy corrections available for some of these. Analytic gradients are available for these SCF functions, for automatic geometry optimization, transition state searches, or reaction path following.