Models including electron correlation in relation to Fock's proposed expansion of the ground-state wave function of He-like atomic ions
Faculty of Sciences. Physics
Physical review : A : atomic, molecular and optical physics. - Lancaster, Pa, 1990 - 2015
, p. 062119,1-062119,4
University of Antwerp
Here attention is first drawn to the importance of gaining insight into Fock's early proposal for expanding the ground-state wave function for He-like atomic ions in hyperspherical coordinates. We approach the problem via two solvable models, namely, (i) the s-term model put forth by Temkin [ Phys. Rev. 126 130 (1962)] and (ii) the Hookean atom model proposed by Kestner and Sinanoglu [ Phys. Rev. 128 2687 (1962)]. In both cases the local kinetic energy can be obtained explicitly in hyperspherical coordinates. Separation of variables occurs in both model wave functions, though in a different context in the two cases. Finally, a k-space formulation is proposed that should eventually result in distinctive identifying characteristics of Fock's nonanalyticities for He-like atomic ions when both electrons are close to the nucleus.