The PSI3 suite of quantum chemical programs is designed for efficient,
high-accuracy calculations of properties of small to medium-sized molecules.
The package's current capabilities include a variety of Hartree-Fock,
coupled cluster, complete-active-space self-consistent-field, and
multi-reference configuration interaction models. Molecular point-group
symmetry is utilized throughout to maximize efficiency.

    * Arbitrarily high angular momentum levels in integrals
       and derivative integrals. (Up to k-type functions have been tested.)
    * Coupled cluster methods including CCSD and CCSD(T) with 
      RHF, ROHF, UHF, and Brueckner orbitals.
    * Determinant-based CI including CASSCF, RAS-CI, and Full CI.
    * Multithreaded integral-direct SCF, MP2, and MP2-R12.
    * Excited state methods: CIS, CIS(D), RPA, and EOM-CCSD.
    * Analytic energy gradients for CCSD with RHF, ROHF, and UHF orbitals.
    * Coupled cluster linear response methods for static and
       dynamic polarizabilities and optical rotation.
    * Diagonal Born-Oppenheimer correction (DBOC) for 
       RHF, ROHF, UHF, and CI wave functions. 

WWW: http://www.psicode.org/