Zero-point averaged dynamics of Arn+He1000: Dopant-size influence on potential-energy surfaces, mass spectra and fragmentation patterns

Abstract

• Effective He-He potentials are little sensitive to the dopant embedded in HNDs. • No Ar + He q fragments detected for Ar n + He 1000 clusters ( n = 3 - 5 ) . • Fast ion ejections, ion trappings, and geminate recombinations for all Ar n + He 1000 . • Inefficient relaxation of Ar 3 + initially excited in its uppermost electronic state. The fragmentation of Ar n + He 1000 ( n = 3 , 5 ) is investigated by zero-point averaged dynamics (ZPAD) and compared with recent results on Ar 4 + He 1000 to investigate the influence of the dopant size. At the core of ZPAD, effective He-He potentials converged for He 1000 and Ar n He 1000 are found alike which suggests that ZPAD simulations on argon-doped helium nanodroplets (HNDs) could restrict to effective potentials obtained for pure HNDs. The fragmentation dynamics of Ar n + He 1000 clusters share a number of similarities, like the absence of Ar + -containing fragments, the occurrence of ion ejections and trappings, Ar n + electronic relaxation typically extending on a picosecond time scale, or primary fragmentation events which are not necessarily representative of the final distribution of fragments. However, Ar 3 + He 1000 clusters also exhibit unexpected behaviors like an inefficient electronic relaxation when the dynamics starts on the uppermost Ar 3 + electronic state which makes the dopant trapped within the droplet.