Differential Cross Sections for Cold, State-to-State Spin-Orbit Changing Collisions of NO(v=10) with Neon

Inelastic scattering processes have proven a powerful means of investigating molecular interactions, and much current effort is focused on the cold and ultracold regime where quantum phenomena are clearly manifested. Studies of collisions of the open shell nitric oxide (NO) molecule have been central in this effort since the pioneering work of Houston and co-workers in the early 1990s. State-to-state scattering of vibrationally excited molecules in the cold regime introduces challenges that test the suitability of current theoretical methods for ab initio determination of intermolecular potentials, and concomitant electronically non- adiabatic processes raise the bar further. Here we report measurements of differential cross sections for state-to-state spin-orbit changing collisions of NO (v = 10, Omega '' = 1.5, and j '' = 1.5) with neon from 2.3 to 3.5 cm(-1) collision energy using our recently developed near-copropagating beam technique. The experimental results are compared with those obtained from quantum scattering calculations on a high-level set of coupled cluster potential energy surfaces and are shown to be in good agreement. The theoretical results suggest that distinct backscattering in the 2.3 cm(-1) case arises from overlapping resonances.

Automated summary

Inelastic scattering processes are powerful in studying molecular interactions, with current focus on the cold and ultracold regime where quantum phenomena are prominent. Challenges in studying collisions of vibrationally excited molecules in the cold regime test the suitability of theoretical methods, while electronically non-adiabatic processes further raise the bar. The experimental measurements of state-to-state spin-orbit changing collisions of NO with neon show good agreement with quantum scattering calculations, indicating possible overlapping resonances leading to distinct backscattering in certain cases.