V. Aquilanti et al., Production, characterization and scattering of a sulfur atom beam: Interatomic potentials for the rare-gas sulfides, RS (R = Ne, Ar, Kr, Xe), PHYS CHEM P, 2(18), 2000, pp. 4081-4088
An intense and stable continuous beam of S atoms and SO radicals is produce
d from a microwave discharge source operating in a SO2-He mixture. The S-at
om beam, characterized by coupling mechanical velocity selection with magne
tic 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 P-3(j), with fine
structure levels j=0, 1, 2 populated according to their degeneracies. Tota
l integral cross-sections for collisions of S (P-3(j)) atoms with Ne, Ar, K
r and Xe have been measured in the beam velocity range 1.0-2.4 km s(-1). Th
e scattering data exhibit a glory interference effect with quenching of the
amplitude of the glory pattern which increases along the rare-gas series f
rom Ne to Xe. The results are analysed to yield a characterization of the s
pherical and anisotropic components of the interaction, providing lengths a
nd strengths of the bonds in the six low lying states of the rare-gas sulfi
des NeS, ArS, KrS and XeS.