Dynamics of acetylene dimers hosted in helium droplets

M. Briant (1, 2) , E. Mengesha (1, 2) , M.-A. Gaveau (2, 1) , B. Soep (1, 2) , J.-M. Mestdagh (1, 2) , L. Poisson (2, 1)

1 LIDyl - Laboratoire Interactions, Dynamiques et Lasers (ex SPAM)
2 DyR - Dynamique Réactionnelle

The CH antisymmetric stretch of the C2H2 moieties in acetylene dimers was explored over the range 3270–3290 cm−1 using the helium nanodroplet isolation (HENDI) technique. This work is part of a general investigation which addresses the dynamical consequences of coupling the deformation motions of weakly bound complexes with a finite size quantum liquid (the helium droplet). The acetylene dimer is attractive from this point of view because one of its deformation coordinates promotes a tunneling isomerization process. A numerical simulation of the observed spectrum allows deriving a set of effective spectroscopic constants which help understanding the dynamical role played by the droplet on the rotation and deformation of the dimer.

Domains: Theoretical and/or physical chemistry; Mechanics of materials [physics.class-ph]; Chemical Physics [physics.chem-ph]

M. Briant, E. Mengesha, M.-A. Gaveau, B. Soep, J.-M. Mestdagh, et al.. Dynamics of acetylene dimers hosted in helium droplets. Physical Chemistry Chemical Physics, 2018, 20 (4), pp.2597 - 2605. ⟨10.1039/C7CP07741F⟩. ⟨cea-01713541⟩