Production, characterization and scattering of a sulfur atom beam: Interatomic potentials for the rare-gas sulfides, RS (R=Ne, Ar, Kr, Xe)†
Abstract
An intense and stable continuous beam of S atoms and SO radicals is produced from a microwave discharge source operating in a SO2–He mixture. The S-atom beam, characterized by coupling mechanical velocity selection with magnetic analysis and detected by a quadrupole mass filter, has been employed in scattering experiments. The transmittance across a Stern–Gerlach magnetic selector, measured mass-spectrometrically at m/z=32 and 34 as a function of the beam velocity and of the deflecting field strength, indicates that the sulfur atoms are
mainly in their electronic ground state 3Pj, with fine structure levels j=0, 1, 2 populated according to their
degeneracies. Total integral cross-sections for collisions of S (3Pj) atoms with Ne, Ar, Kr and Xe have been measured in the beam velocity range 1.0–2.4 km s−1. The