Relativistic coupled cluster calculations on neutral and highly ionized atoms

Relativistic coupled cluster (CC) calculations are performed for the atomic systems Be, Ne(6+), Ar(14+), and Sn(46+). The CC equations through CCSDT are solved within a space spanned by balanced s1/2 gaussian spinors to obtain the s-correlation contributions. No significant contribution of higher correlation effects beyond MBPT (4) is observed within this s1/2-spinor approximation.