Formation of satellite bands in the ionization spectra of extended systems.

Abstract

The ionization spectra of hydrogen clusters converging onto a polymer limit have been investigated by means of one-particle Green's-function calculations. This study focuses on the construction of well-organized correlation bands of shake-up satellites at the expense of the lines in the main (primary) band. Two series of chains have been studied, belonging, in regards to their fundamental Hartree-Fock band gap, to the categories of insulating and semiconducting polymers. Evidence is given for a limitation of the contamination by shake-up lines with the delocalization properties of one-particle canonical states in an insulating situation, whereas a nearly complete fragmentation of main bands into satellites can be expected with polymers of the semiconducting type, as a result of multistates interactions. The onset of this contamination, marking in the ionization spectrum a bifurcation between the one-particle and correlation regimes, can be evaluated from a zeroth-order estimate for the energy threshold of a shake-up transition. Electronic correlation in the neutral ground-state wave function is also shown to increase the breakdown of the one-particle picture of ionization. \textcopyright{} 1996 The American Physical Society.