Electron Propagator Theory and Anion Electronic Structure

Kansas State University, Manhattan KS

Investigators

Abstract

In this project funded by the Theoretical and Computational Chemistry Program of the Chemistry Division and the Americas Program in the Division of International Programs, Ortiz will interpret experimental results on several types of unusual anions using new quantum mechanical methodology. This research effort combines the development of a new generation of electronic structure methods for theoretical modeling of electron attachment and detachment processes with calculations that aim at testing these approaches and at investigating chemical species of practical interest. The computer codes developed will be used to address a wide range of chemical species, including "double Rydberg" anions, zwitterions, dianions, polyanions, and metal oxide clusters. Study of these chemical systems requires the implementation and use of new electron propagator methods that can treat electron correlation in anionic states as well as large orbital relaxation effects that accompany electron detachment. Quasiparticle self-consistent-field methods extend current techniques and satisfy the demands of the systems under study. They also offer an alternative one-electron picture of electronic structure that is complementary to that provided by previously implemented theories. This project involves a collaboration with Ana Martinez and her coworkers at UNAM in Mexico City. The proposed research involves the development of new and improved algorithms for calculating ionization potentials and electron affinities. The challenge to theory is not simply to reproduce a few measured experimental data, but rather to develop a theoretical model that is consistent with known data and capable of predicting consequences subject to subsequent measurement. The propagator method used here, especially in the novel context of a quantitative independent-particle model, is admirably suited to the development of insight and understanding. The resulting new formalisms developed in this project hold promise for enhanced accuracy, improved computational performance, and more straightforward interpretation of the computed data. These methods will be applied to several systems of current experimental interest and will be available to the public for general use. The students who will travel and work with the foreign collaborators in Mexico will gain experience with international collaboration that will enhance their scientific and educational training.