Near-Threshold Inelastic Collisions Using Molecular Beams with a Tunable Velocity
Joop J. Gilijamse,1
Steven Hoekstra,1
Sebastiaan Y. T. van de Meerakker,1*
Gerrit C. Groenenboom,2*
Gerard Meijer1
Molecular scattering behavior has generally proven difficult
to study at low collision energies. We formed a molecular beam
of OH radicals with a narrow velocity distribution and a tunable
absolute velocity by passing the beam through a Stark decelerator.
The transition probabilities for inelastic scattering of the
OH radicals with Xe atoms were measured as a function of the
collision energy in the range of 50 to 400 wavenumbers, with
an overall energy resolution of about 13 wavenumbers. The behavior
of the cross-sections for inelastic scattering near the energetic
thresholds was accurately measured, and excellent agreement
was obtained with cross-sections derived from coupled-channel
calculations on ab initio computed potential energy surfaces.
2 Theoretical Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen, Netherlands.
* To whom correspondence should be addressed. E-mail: basvdm{at}fhi-berlin.mpg.de (S.Y.T.M.); gerritg{at}theochem.ru.nl (G.C.G.)
