Configuration-interaction method with Hylleraas-Gaussian-type basis functions in cylindricalcoordinates: Helium atom in a strong magnetic field

摘要

The energy levels involving the ~10~+, ~1(-1)~+, and ~1(-2)~+ states of the helium atom in strong magnetic fields up to 2.35 × 10~7 T are investigated. Our computational approach is a configuration-interaction (CI). method based on a set of anisotropic Hylleraas-Gaussian orbitals.nonlinearly optimized for different field strength. A detailed comparison between our method and the CI method with the Gaussian-type basis functions in cylindrical coordinates is made. The advantages of the Hylleraas-Gaussian basis over the Gaussian basis are discussed.