Table 1: Ion model key. AST1-AST3: present work ( AUTOSTRUCTURE). HFR1-HFR3: Present work ( HFR). HFR4: HFR calculation by Jacobs et al. (1989). BPR1: Present work ( BPRM). COR: Cornille data set from Kato et al. (1997). SAF: Safronova data set from Kato et al. (1997) and Safronova & Shlyaptseva (1996). MCDF: Multiconfiguration Dirac-Fock calculation by Chen (1986).

Feature	AST1	AST2	AST3	HFR1	HFR2	HFR3	HFR4	BPR1	COR	SAF	MCDF
Orthogonal orbital basis	Yes	Yes	Yes	Yes	No	No	No	Yes	Yes	Yes	Yes
CI from n>2 complexes	No	No	Yes	No	No	Yes	No	No	No	Yes	Yes
Breit interaction	No	Yes	Yes	Yes	Yes	Yes	Yes	No	No	Yes	Yes
QED effects	No	No	No	No	No	No	No	No	No	Yes	Yes
Semi-empirical corrections	No	No	Yes	No	No	Yes	No	No	No	No	No