Calculation of Resonance Energies of 1,3P0, 1,3De, 1,3F0, 1,3Ge, 1,3H0 Doubly Excited States of Helium-Like Ions Systems Associated with n = 2, 3 and n = 4 Hydrogenic Thresholds Using the Hylleraas-Type Wave Functions
In this paper, the kinetic energy, the electrons-nucleus interaction energy, the electron-electron interaction energy and the total energy of doubly excited states of He-like ions are developed in the framework of the variational method using configuration interaction basis with a real Hamiltonian. Correlated Hylleraas-type wave functions are also used in this work in which several lower-lying doubly excited (nl1nl2; l1≠l2) 1,3P0, 1,3De, 1,3F0, 1,3Ge, 1,3H0 intrashell resonances associated with n = 2, 3 and 4 thresholds up to Z = 10 are reported. The results obtained are compared with some theoretical calculations of the available literature.
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