Seminarium fizyki jądra atomowego
Dnia 14 października 2010 odbyło się seminarium pt.
„Coupled-Cluster Theory: From Quantum Chemistry to Applications in Nuclear Physics”
prelegent: prof. Piotr Piecuch (Department of Chemistry, Michigan State University, USA)
Streszczenie: The key to a successful description of many-fermion systems, including atoms, molecules, and nuclei, is an accurate assessment of many-particle correlation effects. One of the most efficient ways of describing many-electron correlations in molecular systems and many-nucleon correlations in nuclei is offered by methods based on the exponential wave function Ansätze defining coupled-cluster theories. This presentation will provide an overview of the wide variety of single- and multi-reference coupled-cluster approaches developed in the context of quantum chemistry, including small molecular systems with dozens of correlated electrons, large molecular systems with hundreds of correlated electrons, and extensions of coupled-cluster methodologies to quasi-degenerate, open-shell, and excited states, and properties other than energy, and the recent applications of the quantum-chemistry inspired coupled-cluster approximations to selected nuclear structure problems, including ground and excited states, and properties of 4He, 16O, and valence systems around 16O, as described by modern nucleon-nucleon interactions (N3LO, CD-Bonn, Argonne V18, VUCOM), and heavier nuclei, including 55Ni, 56Ni, and 57Ni, as described by the effective Hamiltonians used in traditional shell-model calculations. The successes as well as challenges facing coupled-cluster approaches, as applied to the electronic and nuclear structure problems, will be discussed.