Ds. Kim et al., NUCLEAR-CHARGE EFFECT IN PHOTOELECTRON EJECTION FROM THE 1S2S2P P-4 STATE OF HE-,LI, AND BE+, Journal of the Korean Physical Society, 29(4), 1996, pp. 440-446
The photoionization cross sections of Li and Be+ from the excited 1s2s
2p P-4 state, which have not been explored previously, are calculated
for ejection of each of the electrons using multi-configuration Hartre
e-Fock (MCHF) wave functions and compared with a recent study on the p
hotodetachment of He-, focusing on the nuclear charge effect in this i
soelectronic sequence. The use of MCHF wave functions is good for Li a
nd Be+, but crucial for He-. The behavior of the photoionization cross
sections of Li and Be+ are quite different from the photodetachment o
f He-. and Be+ also differs from Li. The maximum in the Be+ cross sect
ion occurs at the 2s threshold while for Li it is at the 2p threshold.
The results are explained in terms of important correlations in the w
ave functions and how they are modified as a function of nuclear charg
e.