Fragmentation of sputtered Si n O m + clusters: Release kinetic and dissociation energies

Photochemical properties of a potential interstellar dust precursor: the electronic spectrum of Si3O2+

“…Significantly, our computed binding energy for SiO loss is much higher and probably more reliable than those values inferred in a rather indirect analysis of experimental kinetic energy release data ( D 0 = 0.75 and 1.06 eV). 44…”

“…42,43 In addition, the dissociation into Si 2 O + and SiO was predicted to be the lowest-energy fragment channel. 42 The analysis of the kinetic energy release upon metastable decay of Si 3 O 2 + into SiO using the Klots evaporation ensemble and Rice-Ramsperger-Kassel (RRK) models yielded dissociation energies of 0.75 and 1.06 eV, respectively, 44 much lower than those calculated for a variety of Si n O m + ions including Si 3 O 2 + (2–4 eV). 42…”

Decay rate constants of sputtered vanadium oxide clusters

“…The emissions and fragmentation of sputtered were investigated in an inverse geometry double focusing secondary ion mass spectrometer [3] using the procedure described in [4][5][6][7]. clusters were generated by bombarding V targets with Xe + ions at an angle of 45° while the surface was scanned over a 1.5 × 1.5 mm field and O 2 was bled into the chamber up to pressures of 4-5 × 10 -3 Pa.…”

“…A spread of excitation energies δN/δE B = f(E B ) [8,9] was observed in the sputtered clusters, which were found to decay along the route from target to detector [3][4][5][6][7]. Fragmentation study relies on the availability of zones in the experimental setup [3] in which direct registration of secondary ion decay is possible in various time spans.…”

“…Our method for estimating the average rate con stant k of unimolecular fragmentation of sputtered clusters [4,5] was based on comparing the number of decays that occurred over times of flight Δt 1 and Δt 2 through field free zones S 1 and S 2 of the mass spec trometer, assuming that the number of metastable clusters ΔN 1 and ΔN 2 that can fragment over these times is proportional to the initial numbers N 1 and N 2 of the ions entering these zones.…”