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Abstract: We have measured the kinetic energy release distributions for unimolecular C2 loss from singly and multiply charged endohedral La@C80 z+ and La@C80 z+ ions for charge states z =1–3. Using finite heat bath theory, we deduce the dissociation energies for loss of C2. The charge state z has no statistically significant effect on the dissociation energies. The dissociation energies of endohedral fullerene ions are larger than those of the corresponding empty fullerene ions by a few tenths of an electron volt, but the differences are barely statistically significant. The small differences also imply that the complexation energies of La@C n z+ and La@C n −2 z+ are identical within the experimental errors, for n =80 and 82 and all charge states. [Copyright &y& Elsevier]

Abstract: Doubly charged ions produced by electron impact ionization of toluene (C7H8) show metastable unimolecular dissociation into two singly charged fragments. A high-resolution double focusing mass spectrometer (reversed Nier–Johnson type BE geometry) was used to monitor these decomposition reactions. We have identified four competing charge separation channels. The mass-analyzed ion kinetic energy (MIKE) technique was used to determine mean values of the kinetic energy release (KER). We obtained values of the average KER for the charge separation reactions of ranging from 2.5 to 3.5eV. [Copyright &y& Elsevier]

Abstract: Metastable fractions for the dissociation of fullerene cations have been measured in a three-sector-field mass spectrometer. They have been determined with the same experimental setup as the kinetic energy release data published recently. A statistical model which includes cooling by radiation as required by the timescale of the experiment is used to deduce dissociation energies from the metastable fractions. The results are compared with values extracted from our kinetic energy release data and other experiments. [Copyright &y& Elsevier]

Abstract: Metastable ions C3HnN+ (n =1, 2 or 3) and C2H2 + produced by electron impact on the neutral C3H3N (acrylonitrile) undergo metastable decay reactions resulting in the fragment ions C3HmN+ (m =1, 2) or C2H2 +. We have monitored these reactions in a double focusing mass spectrometer of reversed B-E geometry. To identify the fragment ions and determine their kinetic energy release distribution (KERD), the mass-analyzed ion kinetic energy (MIKE) scan technique was utilized. For the above mentioned ions we obtained average KER values ranging from 9 up to 23meV. Moreover, the fractions of decaying ions were measured. We have found the existence of two states of the metastable C2H2 + ion, one with a short life time of about 0.27μs and the other one which is most likely a completely stable ion state. [Copyright &y& Elsevier]

Abstract: Doubly charged ions produced by electron impact ionization of toluene undergo metastable decomposition. We have determined decay channels for and the average kinetic energy release (KER) by applying the MIKE scan technique. We observe several reactions that have not been reported previously, including H2 elimination from . The KER distribution for H2 loss shows no evidence for a reverse barrier. The average KER is <0.1 eV; it exhibits a distinct time dependence and isotope effect. On the other hand, some charge separation reactions reported previously in the literature are likely due to isotopic interference. [Copyright &y& Elsevier]

Abstract: The synthesis of silver nanoparticles via UV irradiation of AgNO3 solutions was controlled by using UV–vis absorption spectra and TEM (transmission electron microscope) images. The UV–vis absorption method is good enough for the general control of synthesis process, and TEM images give us information about size of formed species. For investigated solutions of silver nitrate in ethanol and water, we observed formation of large nanoparticles (size about 100nm) and nanorods (100nm in length). Moreover, there was effort to confirm evidence of formation of these particles by using TOF mass spectrometer. Due to laser desorption/ionization process there is only evidence of small silver nanoparticles Ag x , x ≤4 (clusters), and variety of silver compounds Ag x N y O z (x ≤5, y ≤2, z ≤3). [Copyright &y& Elsevier]