Lecture

Configuration Interaction II: Correlation Energy and CSF's

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In course

CH-353: Introduction to electronic structure methods

Repetition of the basic concepts of quantum mechanics and main numerical algorithms used for practical implementions. Basic principles of electronic structure methods:Hartree-Fock, many body perturbation theory, configuration interaction, coupled-cluster t ...

Description

This lecture delves into the calculation of correlation energy using Configuration Interaction methods, focusing on the contributions from doubles, triples, and quadruples, and the number of Configuration State Functions (CSF's) required for accurate results. The instructor discusses the importance of different levels of excitations and symmetries in limiting the number of determinants. Additionally, the lecture covers the significance of dynamic correlation and low-lying excited states in accurate electronic structure calculations, emphasizing the role of perturbation theory in handling electron correlation effects.

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Instructor

Ursula Röthlisberger

U. Röthlisberger was born in Solothurn (Switzerland). In 1988 she made her diploma in Physical Chemistry in the group of Prof. Ernst Schumacher at the University of Berne (Switzerland). Her Ph.D. thesis was done in collaboration with Dr. Wanda Andreoni at the IBM Zurich Research Laboratory in Rüschlikon. After finishing her Ph.D in 1991 she spent some time as a postdoctoral research assistant at the IBM Research Lab. From 1992-1995 she was a postdoctoral research assistant in the group of Prof. Michael L. Klein at the University of Pennsylvania in Philadelphia (USA). In 1994 she was awarded an advanced researcher fellowship (Profil 2) from the Swiss National Science Foundation. Before starting her Profile 2-fellowship she spent another year as postdoctoral research assistant in the group of Prof. Michele Parrinello at the Max-Planck-Institute for Solid State Physics in Stuttgart, Germany. In 1996 she moved as Profile 2-fellow to the ETH in Zurich, hosted by the group of Prof. Wilfred F. van Gunsteren. In 1997 she became Assistant Professor of Computer-Aided Inorganic Chemistry at the ETH Zurich.

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