Rotationally inelastic scattering of ND₃ with H₂ as a probe of the intermolecular potential energy surface

Differential cross sections (DCSs) are reported for rotationally inelastic scattering of ND₃ with H₂, measured using a crossed molecular beam apparatus with velocity map imaging (VMI). ND₃ molecules were quantum-state selected in the ground electronic and vibrational levels and, optionally, in the j^±k = 1₄^- rotation-inversion level prior to collisions. Inelastic scattering of state-selected ND₃ with H₂ was measured at the mean collision energy of 580 cm^-1 by resonance-enhanced multiphoton ionisation spectroscopy and VMI of ND₃ in selected single final j'^±k' levels. Comparison of experimental DCSs with close-coupling quantum-mechanical scattering calculations serves as a test of a recently reported ab initio potential energy surface. Calculated integral cross sections reveal the propensities for scattering into various final j'^±k' levels of ND₃ and differences between scattering by ortho and para H₂. Integral and differential cross sections are also computed at a mean collision energy of 430 cm^-1 and compared to our recent results for inelastic scattering of state-selected ND₃ with He.