Imaging scattering resonances in low-energy inelastic ND3-H2 collisions
Stach E J Kuijpers1, David H Parker1, Jérôme Loreau2
1Radboud University, Institute for Molecules and Materials, Nijmegen, the Netherlands.
Nature Communications
|August 5, 2025
Summary
Quantum scattering resonances in low-temperature molecular collisions were observed for a six-atom system (ND3-H2/HD). This breakthrough extends experimental capabilities to polyatomic molecules, revealing strong resonances in integral and differential cross sections.
Area of Science:
- Quantum mechanics
- Molecular collisions
- Spectroscopy
Background:
- Scattering resonances are key quantum effects in molecular collisions.
- Previous experimental studies were limited to systems with at most four atoms.
- Studying larger, chemically relevant systems is crucial but challenging.
Purpose of the Study:
- To experimentally and theoretically investigate scattering resonances in state-to-state inelastic collisions.
- To extend the study of scattering resonances to a six-atom polyatomic symmetric top molecule system (ND3-H2/HD).
- To probe the quantum nature of collisions in more complex molecular systems.
Main Methods:
- Joint experimental and theoretical study of ND3-H2/HD collisions.
- Measurements across a collision energy range of 0.5-25 cm⁻¹.
- High-resolution differential cross section measurements using vacuum ultraviolet (VUV) laser ionization.
- Theoretical calculations using a potential energy surface at the CCSD(T) level with CCSDT(Q) corrections.
Main Results:
- Strong scattering resonances were resolved in the integral cross sections for the ND3-H2/HD system.
- High-resolution differential cross sections were successfully measured.
- Experimental data were accurately reproduced by theoretical predictions.
Conclusions:
- This study successfully extends the experimental observation of scattering resonances to a six-atom polyatomic molecule.
- The findings validate advanced theoretical methods for describing complex molecular collisions.
- This work opens new avenues for exploring quantum effects in chemically relevant systems.
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