Multidimensional Surface Topology and Berry Force Effects in NO–Alkane Collisions: Insights from Infrared Spectroscopy and Velocity Map Imaging

Herein, we will discuss the infrared spectroscopy and dynamics of nitric oxide (NO) collision complexes with methane, ethane, propane, and n-butane to reveal how Jahn–Teller and pseudo Jahn–Teller effects shape the bimolecular collision mechanisms. Using infrared action spectroscopy and velocity map imaging (VMI), we uncover the vibrational predissociation pathways as the alkane chain length increases. Furthermore, the NO product state distributions indicate a plausible Berry force that may impact the scattering outcomes. The observed ion images and spin-polarized product distributions offer mechanistic insights into the energy exchange and dissociation pathways, establishing how coupled nuclear-spin dynamics in the vicinity of an avoided crossing modulate the NO–alkane collision outcomes. These findings provide a benchmark for the role of multidimensional surface topology in controlling radical–molecule collision dynamics.