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    Absorption and Emission Studies of Solubilization in Micelles Part 4.—Studies on Cationic Micelles with added Electrolyte and on Lecithin Vesicles: Excimer Formation and the Ham Effect
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1977, 73 (12), 1977) Dorrance, Richard C; Hunter, Tom F
    The diffusion of pyrene, and thus other large planar aromatic molecules, is shown to take place in a shell close to the double-layer of cationic micelles. Perturbation of the pyrene π-electrons is demonstrated by vibronic band intensity comparisons, i.e. the Ham effect, and used to discuss dielectric leakage into the hydrophobic part of the micelle. Aggregation numbers and pyrene diffusional characteristics are described for lecithin vesicles. The effect of added electrolyte (NaBr) on aggregation numbers of cationic micelles is determined and contrasted with the concomitant changes in pyrene diffusion.
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    Far Ultraviolet Solution Spectroscopy of the Iodide Ion
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1977, 73 (07), 1977) Fox, Malcolm F; Hayon, Elie
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    Adsorption of Carbon Monoxide on Copper (100) Studied by Photoelectron Spectroscopy and Low Energy Electron Diffraction
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1978, 74(3), 1978) Isa, Saadoon A.; Joyner, Richard W.; Roberts, M. Wyn
    By combining u.v. and X-ray photoelectron spectroscopy with low energy electron diffraction, Cu(100) has been shown to adsorb carbon monoxide at 295 K. Adsorption, although molecular, has distinctly different spectroscopic characteristics from adsorption at 80 K. The oxygen (1s) binding energy is 1.3 eV lower at 295 K than at 80 K, the carbon 1s binding energy is also lower. The sticking probability is ∼10–6 at 295 K although close to unity at 80 K, and the energy of desorption is greater for the room temperature state. The LEED pattern, (√2 ×√2)R45° is the same as observed at 80 K (for θ < 0.5) but the maximum coverage is substantially smaller at 295 K (θ∼ 0.3) and the diffraction spots more diffuse. At 80 K the photoelectron spectroscopy and LEED data are similar to those observed previously. Changes in the u.v. induced spectra with increasing CO coverage are shown to reflect the onset of LEED “compression structures” rather than the presence of two adsorbed phases of carbon monoxide. We suggest that the existence of two distinct types of CO bonding on copper (100), (at 295 and 80 K) is a consequence of the molecule acting more as an electron acceptor, (“COδ–”) at 295 K and more like an electron donor, (“COδ+”) at 80 K. The presence of a chemisorption level 1.5 eV below the Fermi edge, i.e. in the s-band region of the spectrum, is interpreted as being due to reorganisation of metal s and d electrons which is in keeping with the transition metal-like characteristics of the adsorption at 295 K.
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    Different Species of Hydrogen Chemisorbed on Raney Nickel Studied by Neutron Inelastic Spectroscopy
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1977, 73 (1), 1977) Renouprez, A. J.; Fouilloux, P.; Coudurier, G.
    The chemisorption of hydrogen on Raney nickel has been studied by neutron inelastic spectroscopy at high energy transfer. The main vibration levels at 120 and 140 meV are interpreted as being produced by multi-bonded surface species. A weak band also appears around 280 meV, superposed on the harmonic of the 140 meV peak, which can be attributed to the vibration of a linear form Ni—H. This interpretation is supported by the optical spectra of transition metal hydrides of known structure.
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    Electron Donor Sites on the Surface of Magnesium Oxide Powder studied by Electron Spin Resonance Spectroscopy
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (12), 1974) Cordischi, D.; Indovina, V.; Cimino, A.
    The electron donor properties of MgO powders, activated in vacuo in the temperature range 300–1200 K have been investigated by adsorption of nitrobenzene and some of its para substituted derivatives. The results confirm that the donor properties of MgO are an intrinsic property of the surface, being practically independent of impurity. Two types of nitrobenzene radical were detected: the first one, formed on low temperature activated samples (<1200 K), is the nitrobenzene radical anion interacting with surface protons; the second one, observed on high temperature (1200 K) activated MgO, is the “free” radical anion. No correlation between electron affinity of the adsorbed molecules and radical surface concentration was found. The proton affinity of the anion radical has to be taken into account to rationalize the results. A model of the electron donor surface site consisting of a dual site (O2–cus, OH–) is presented. The effect of adding Ni2+ ions in solid solution has also been examined.