MCHF studies of partial photoionization cross section of atomic fluorine

Abstract

We present results of a theoretical investigation of the partial and total photoionization cross sections between the 1 D and 1 S thresholds of atomic fluorine using the multiconfiguration Hartree-Fock method of bound and continuum wavefunctions. The 2p 4 ( 1 S)ns, md series observed by an experiment through their decay into the allowed 2p 4 ( 3 P)kl and 2p 4 ( 1 D)kl ionization channels are carefully identified. The 2s2p 6 2 S resonance is seen to interact strongly with the nearby 2p 4 ( 1 S)4s 2 S resonance. The results of the partial cross sections are first compared with the experimental observations. The total cross sections are compared with the available experimental and theoretical data. The energy positions of the resonance series 2p 4 ( 1 S)ns, md as well as 2s2p 6 2 S excitation are found to be in very good agreement with the experimental observations.

Autoionizing resonances in time-dependent density functional theory

“…Fits are routinely made for the Fano parameters q, G and o r for a given cross-section obtained from experiment or theory, i.e. eqn (2)(3)(4) are not typically used to calculate these quantities, rather, they are extracted from experimental or theoretical data. Although we will only use the simplest type of resonance in the present paper, we do note that Fano's analysis has been generalized in several directions, 30,32,33 e.g.…”

“…For atoms, one of the more successful approaches is multi-configuration Hartree-Fock [3]; this accounts for electron correlation and core polarization accurately enough to describe atomic resonances eg. * Electronic address: nmaitra@hunter.cuny.edu in halogens [4]. For molecules, Ref.…”

“…in halogens. 4 For molecules, ref. 5 studied the relationship between interatomic distances and resonance positions using a minimal-basis static exchange method.…”