Browsing by Subject "Dissociation"

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    Dynamics of the D2 + Ni(100) collision system: Analysis of the reactive and inelastic channels
    (2001) Böyükata M.; Güvenç Z.B.; Jackson B.; Jellinek J.
    The reactive and scattering channels of the D2(v, j) + Ni(100) collision system are studied using quasiclassical molecular dynamics simulations. The interaction between the D2 and the atoms of the surface is modeled by a LEPS (London-Eyring-Polani-Sato) potential energy function. The molecule is aimed at three different impact sites (atop, bridge, and center) of a rigid Ni(100) surface along the normal direction with various collision energies ≤1.0 eV. Dissociative chemisorption probabilities are computed for different rotational states of the molecule. Probability distributions of the final rovibrational states of the ground-state D2 molecule scattered from those impact sites are also computed as a function of the collision energy. Higher collision energy results in excitation of higher rotational and/or vibrational states of the scattered molecule. At collision energies below 0.1 eV an indirect dissociation mechanism (through molecular adsorption) dominates the reaction.
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    Optical properties of Cu implanted ZnO
    (2006) Cetin A.; Kibar R.; Ayvacikli M.; Can N.; Buchal Ch.; Townsend P.D.; Stepanov A.L.; Karali T.; Selvi S.
    Nanoparticles of Cu have been made in zinc oxide crystals by ion implantation. The Cu ions were implanted at 400 keV into the (0 0 0 1) face of a single crystal. After implantation and after post-irradiation annealing there are numerous changes in the luminescence responses which include a variety of green and yellow emission bands. Following annealing at temperatures up to 1000 °C a green luminescence near 525 nm was observed which has been associated with the isolated Cu ions. The changes between as implanted and annealed luminescence signals suggests that the implants generate clustering or nanoparticle formation of Cu but anneals dissociate them. © 2006 Elsevier B.V. All rights reserved.
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    Speciation of [Cp*2M2O5] in polar and donor solvents
    (2013) Sözen-Aktaş P.; Del Rosal I.; Manoury E.; Demirhan F.; Lledõs A.; Poli R.
    The speciation of compounds [Cp*2M2O 5] (M=Mo, W; Cp*=pentamethylcyclopentadienyl) in different protic and aprotic polar solvents (methanol, dimethyl sulfoxide, acetone, acetonitrile), in the presence of variable amounts of water or acid/base, has been investigated by 1H NMR spectrometry and electrical conductivity. Specific hypotheses suggested by the experimental results have been further probed by DFT calculations. The solvent (S)-assisted ionic dissociation to generate [Cp*MO2(S)]+ and [Cp*MO 3]- takes place extensively for both metals only in water/methanol mixtures. Equilibrium amounts of the neutral hydroxido species [Cp*MO2(OH)] are generated in the presence of water, with the relative amount increasing in the order MeCN≈acetone