TY - JOUR

T1 - The calculation of ion fractions in LEIS

AU - Verbist, G.

AU - Brongersma, H. H.

AU - Devreese, J. T.

PY - 1992/2/2

Y1 - 1992/2/2

N2 - We discuss different ways of calculating ion fractions for LEIS-type experiments: (i) parametrizations, and (ii) quasi-ab-initio models. Among the different parametrizations of the neutralization rates the Hagstrum, Godfrey-Woodruff and the unified model are compared. For surfaces containing different types of atoms, e.g. NaCl, it is not possible to determine the neutralization constants uniquely. This is related to the use of relative ion fractions. For the absolute ion fractions there is a convincing agreement between DISC-experiments for He+ → Si scattering and a theoretical calculation on the basis of the quasi-ab-initio Muda-Newns model.

AB - We discuss different ways of calculating ion fractions for LEIS-type experiments: (i) parametrizations, and (ii) quasi-ab-initio models. Among the different parametrizations of the neutralization rates the Hagstrum, Godfrey-Woodruff and the unified model are compared. For surfaces containing different types of atoms, e.g. NaCl, it is not possible to determine the neutralization constants uniquely. This is related to the use of relative ion fractions. For the absolute ion fractions there is a convincing agreement between DISC-experiments for He+ → Si scattering and a theoretical calculation on the basis of the quasi-ab-initio Muda-Newns model.

UR - http://www.scopus.com/inward/record.url?scp=0347715551&partnerID=8YFLogxK

U2 - 10.1016/0168-583X(92)95535-Y

DO - 10.1016/0168-583X(92)95535-Y

M3 - Article

AN - SCOPUS:0347715551

SN - 0168-583X

VL - 64

SP - 572

EP - 575

JO - Nuclear Instruments and Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms

JF - Nuclear Instruments and Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms

IS - 1-4

ER -