Atomic, Molecular, and Optical Theory Group
Electron-molecule and electron-atom collisions initiate and drive almost all the relevant chemical processes associated with radiation chemistry in the environment and other environmental remediation, radiation damage to living systems, plasma processing of materials for microelectronic devices and everyday lighting technology. In spite of the importance of these fundamental processes, only fragments of the fundamental chemistry and physics are well understood, and only a few of the required cross sections and reaction rates for the multitude of important molecules are known with confidence.
The Atomic and Molecular Theory group at Berkeley Lab is developing new theoretical approaches to attack a broad range of problems in 'Electron-Driven Chemistry', using large-scale computation as a tool for studying electron and photon interactions with atoms and molecules. The techniques of modern computation quantum chemistry are being combined with variational scattering theory methods to provide a practical approach to studying low-energy electron collisions with polyatomic targets. The complex Kohn variational method has provided the framework for our studies of continuum electronic structure. We are interested not only in the fixed-nuclei electronic scattering problem but also in the nuclear dynamics that accompanies such collisions. Of particular current interest in the group are resonant electron collisions with polyatomic molecules and the mechanisms whereby electronic energy is transferred into nuclear degrees of freedom, including near-threshold and resonant vibrational excitation of polyatomics and dissociative electron attachment.
The Atomic and Molecular Theory group has also been at the forefront of developing first-principles computational approaches for detailed studies of fundamental collisional ionization problems in atomic systems. Our recent research efforts using exterior complex scaling and massively parallel computation have led to the first solution of the long-standing problem of a complete quantum description of collisional breakup of a quantum three-body system. Current efforts are focused on extending these studies to atomic targets with two active electrons and on developing practical schemes for studying double photoionization of atoms and molecules.
The Group's activities at Berkeley Lab are co-directed by Dr. C. William McCurdy and Dr. Thomas N. Rescigno, both Senior Scientists in Chemical Sciences at LBNL. The group recieves its principal funding through the US DOE Office of Basic Energy Science, Division of Chemical Sciences and has strong collaborative ties with investigators in the Department of Applied Science at UC Davis.