Dynamics of the S(1D2)+HD(j=0) reaction at collision energies approaching the cold regime: a stringent test for theory.

Manuel Lara (1) , Simon Chefdeville (2) , Kevin M Hickson (2) , Astrid Bergeat (2) , Christian Naulin (2) , Michel Costes (2) , Jean-Michel Launay (3)

1 Departamento de Química Física Aplicada
2 ISM - Institut des Sciences Moléculaires
3 IPR - Institut de Physique de Rennes

We report integral cross sections for the S(1D2)+HD(j=0)→DS+H and HS+D reaction channels obtained through crossed-beam experiments reaching collision energies as low as 0.46 meV and from adiabatic time-independent quantum-mechanical calculations. While good overall agreement with experiment at energies above 10 meV is observed, neither the product channel branching ratio nor the low-energy resonancelike features in the HS+D channel can be theoretically reproduced. A nonadiabatic treatment employing highly accurate singlet and triplet potential energy surfaces is clearly needed to resolve the complex nature of the reaction dynamics.

Mots clés: Molecular physics; Quantum dynamics; Cold and ultra-cold collisions

Domaines: Biophysique [physics.bio-ph]; Biophysique

Manuel Lara, Simon Chefdeville, Kevin M Hickson, Astrid Bergeat, Christian Naulin, et al.. Dynamics of the S(1D2)+HD(j=0) reaction at collision energies approaching the cold regime: a stringent test for theory.. Physical Review Letters, 2012, 109 (13), pp.133201. ⟨10.1103/PhysRevLett.109.133201⟩. ⟨hal-00856178⟩