Accurate Computation of Resonant States of Three-Electron Atomic Systems : A Complex Scaled Hylleraas CI Method

Abstract

RESUMEN: Los estados doble y triplemente excitados de sistemas trielectrónicos, constituyen un problema coulombiano de cuatro cuerpos, el cual es altamente correlacionado. Para su tratamiento hemos desarrollado un programa de Interacción de Configuraciones (CI) basado en funciones de Hylleraas ( ´ Hy), para momento angular y de espín arbitrarios. El computo de resonancias se ha implementado mediante un escalado complejo uniforme (UCS). Nuestro código nos permite calcular estados resonantes del ion negativo del Helio con la mayor precision posible.

ABSTRACT: Doubly and triply excited states of three-electron systems provide the case for a highly correlated fourbody Coulomb problem. We have developed a sophisticated three-electron Configuration Interaction (CI) code based on explicitely correlated Hylleraas (Hy) functions for arbitrary total angular momentum and spin, which has been implemented with an uniform complex scaling (UCS) method to deal with resonant states. At present, this UCS-HyCI tool allows us to perform computations to uncover resonant states of the Helium negative ion, with the highest accuracy possible