Hyperfine structure constants of (d+s)3 states in La I and the Zr II and Hf II isoelectronic sequences

Abstract

ABSTRACT:Accurate results for hyperfine structure HFS constants of d q s states often require the inclusion of both correlation and relativistic effects. Without these, Dirac᎐Fock HFS constants may have the wrong sign, the energies of uppermost d n levels may be wrong by over 1 eV. Here, we demonstrate that these problems persist well into an isoelectronic sequence, and identify the principle configurations needed to achieve accurate results.

Critical analysis of the methods of interpretation in the hyperfine structure of free atoms and ions: case of the model space (5d+6s)3of the lanthanum atom

“…Experimental and corrected values of the hfs A and B constants (MHz) for the even-parity energy levels of a lanthanum atom. The values of A th and B th are taken from Childs and Nielsen (MCDF method) [13] a , from Beck (MCDF and RCI method) [45] b and from Karacoban (MCHF method) [46] c . The experimental values are taken from Ting [44] d , Childs and Goodman [26] e , Childs and Nielsen [13] a , Furmann et al [28,29] f and from our measurements.…”

Relative cross sections for the electron impact single detachment on Li

“…The 40 meV energy resolution of our experimental set-up around threshold is not the limiting factor in that case. Some computations were performed on that subject by Beck [36] who considered Li 2− (1s 2 2p 3 4 S), and found a sign for the orbital eigenvalue not compatible with the stability of this dianion.…”

Parametric study of hyperfine structure of Zr II even-parity levels

“…Why this study is limited only to two cases: J = 1/2 and J =3/2? This work was extended [15] to Zr II Isoelectronic sequences: Hf II,Nb III, Ta III, Mo IV, W IV and La I. He showed that when using Dirac-Fock calculations one has to take into account both correlation and relativistic effects; otherwise calculated hfs constants may have wrong signs.…”