title: Heating a bowl of single-molecule-soup: structure and desorption energetics of water-encapsulated open-cage [60] fullerenoid anions in the gas-phase.
abstract: The gas-phase unimolecular decay kinetics of an anionic, open-cage [60] fullerene derivative encapsulating one water molecule is studied by means of black-body IR radiation induced dissociation (BIRD) in the temperature programmable ion trap of a Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometer. The primary reaction channel observed is escape of the water molecule from the fullerenoid bowl. The rate constants for this water loss as a function of temperature are evaluated using the Arrhenius equation to yield an activation energy of 104 ± 4 kJ mol(-1). A complementary ion mobility spectrometry study contrasting the water-encapsulated and the empty fullerene cages finds identical collision cross sections to within experimental error-supporting the structural assignment of this gas-phase anion as an endohedral (i.e. encapsulated) species. Both experiments were compared with quantum-chemical computations which well-describe the transition state for water desorption and the concomitant binding and activation energies.
authors.affiliation: Abteilung für Physikalische Chemie Mikroskopischer Systeme, Institut für Physikalische Chemie, Karlsruher Institut für Technologie (KIT), P.O. Box 6980, D-76049 Karlsruhe, Germany. oliver.hampe@kit.edu
authors.forename: Oliver
authors.initials: O
authors.lastname: Hampe
authors.forename: Tatjana
authors.initials: T
authors.lastname: Karpuschkin
authors.forename: Matthias
authors.initials: M
authors.lastname: Vonderach
authors.forename: Patrick
authors.initials: P
authors.lastname: Weis
authors.forename: Yuming
authors.initials: Y
authors.lastname: Yu
authors.forename: Liangbing
authors.initials: L
authors.lastname: Gan
authors.forename: Wim
authors.initials: W
authors.lastname: Klopper
authors.forename: Manfred M
authors.initials: MM
authors.lastname: Kappes