Ionization Limits and Upper Levels in P-XIV and in Cl-XVI

Abstract In this study, the ground state and excited state ionization limits with and without consideration of relativistic effects are computed for a helium-like iso-spectrum level sequence for the following configurations: 1s 2 S 0 1 , 1s3s S 0 1 , 1s3p P 0 o 3 , 1s2p P 1 o 1 , 1s3p P 1 o 1 , 1s4p P 1 o 1 , 1s5p P 1 o 1 , 1s6p P 1 o 1 , 1s3p P 1 o 3 , 1s3s S 1 3 , 1s4s S 1 3 , 1s3d D 2 1 , 1s3d D 2 1 , 1s5d D 2 3 , 1s2d P 2 o 3 , 1s3d D 3 3 , 1s4d D 3 3 , 1s5d D 3 3 for nuclear charge Z . The non-relativistic ionization limits are derived from the weakest bound electron potential model, and relativistic corrections are included by using the Breit-Pauli approximation, which has also been applied to the computed relativistic ionization limits at high-order polynomials in the effective nuclear charge Z ′ . This study suggests two hundred and seventy-two excited states ionization potentials with and without a relativistic effect. Furthermore, it fills the gap of thirty-four excited state ionization potentials and their energies for the following configurations: 1s3s S 0 1 , 1s3p P 0 o 3 , 1s2p P 1 o 1 , 1s3p P 1 o 1 , 1s4p P 1 o 1 , 1s5p P 1 o 1 , 1s6p P 1 o 1 , 1s3p P 1 o 3 , 1s3s S 1 3 , 1s4s S 1 3 , 1s3d D 2 1 , 1s3d D 2 1 , 1s5d D 2 3 , 1s2d P 2 o 3 , 1s3d D 3 3 , 1s4d D 3 3 , 1s5d D 3 3 in P − X I V and, C l − X V I which is very onerous to compute owing to foreign-level configuration mixing causing high perturbation, are currently not listed at NIST. This work shows excellent agreement between the computed values and NIST values. The yield ionization limits I n r and I N , Z ′ departing from NIST ones by not more than 1.0 eV and 0.00001 eV, respectively. Both sets of data reported are precise up to 4 decimal place.