Eur. Phys. J. Plus (2018) 133: 379
https://doi.org/10.1140/epjp/i2018-12192-9

Regular Article

Energy levels and oscillator strengths for carbon isoelectronic sequence from C I to Ne V

¹ Department of Physics and Astronomy, College of Sciences, King Saud University, PO Box 2455, 11451, Riyadh, Saudi Arabia
² Groupe de Recherche en Physique Atomique et Astrophysique (GRePAA), INSAT, Centre Urbain Nord, University of Carthage, Tunis, Tunisia

^* e-mail: nbennessib@ksu.edu.sa

Received: 28 May 2018
Accepted: 6 August 2018
Published online: 21 September 2018

Abstract

Energy levels and oscillator strengths for the first five elements of the carbon isoelectronic sequence (C I, N II, O III, F IV and Ne V) have been calculated using the Hartree-Fock pseudo-relativistic (HFR) and the Thomas-Fermi-Dirac-Amaldi (TFDA) approaches. The configuration expansion containing the eight configurations, 2s² 2p², 2s 2p³, 2s² 2p 3s, 2s² 2p 3p, 2s² 2p 3d, 2s² 2p 4s, 2s² 2p 4p and 2s² 2p 5s, has been used. Our presented results have been compared with other theoretical and experimental data. The analysis of the weighted oscillator strengths trends allows us to estimate values of missing data along this isoelectronic sequence. We present an analytic form of the weighted oscillator strengths and give an example of its use for interpolating and extrapolating values for the carbon isoelectronic sequence.