Quantum Theory Project ,University of Florida Gainesville United States
Accomplishments made during this reporting period include the further development of multi-reference Fock space coupled-cluster theory, with emphasis on its relationship to the equation-of-motion CC method for excited states. The importance of these studies is that each approach bas some advantages and disadvantages. The hope is to combine them into one method with the best of both. In addition this period includes our introduction of the new nCC hierarchy which means it bas to be exact for n electrons, but is computationally simpler than the corresponding traditional CCSD, CCSDT, CCSDTQ, etc. hierarchy. The seamless connection between correlated wave function theory and the effective, one-particle density functional theory which leads to ab initio density dft bas been further developed. Also discussed is further work on the massively parallel ACES III program system.