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    Structure and Catalytic Activity of Iron Oxide and Magnesium Oxide Solid Solutions: Part 3- E.S.R. Characterization
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1977, 73 (1), 1977) Cordischi, Dante; Pepe, Franco; Schiavello, Mario
    Magnesium oxide + iron oxide, fired both in air and in a reducing atmosphere, and magnesium oxide + iron oxide + lithium oxide (up to 1 % atomic Fe) were investigated by e.s.r. spectroscopy. The effects of outgassing at various temperatures and of N2O decomposition on the e.s.r. spectra are discussed in terms of surface redox processes. The incipient formation of the spinel phase, MgeFe2O4, and its precipitation, at the highest outgassing temperatures adopted, were readily studied by the e.s.r. technique. The hypotheses previously proposed on the modification of the catalyst solid state, occurring during N2O decomposition and/or in the vacuum treatment, are confirmed by the present study. Further details are also given.
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    Reactivity and catalytic activity of copper chlorides: Part 4.—Electrical properties and acceptor levels produced in CuCl by Cl2 gas
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (1-6), 1974) Harrison, Lionel G.; Prasad, Mahendra
    Studies of electrical conductivity, thermoelectric power and transport numbers in CuCl, pure or after exposure to Cl2 gas, in the range 24–240°C, have shown that all phenomena observed are caused by electronic rather than ionic conduction, except in pure CuCl above about 140°C. Two acceptor levels are identified, at 0.51 and 0.88 eV above the valence band. The former is attributed to cation vacancies; the latter, tentatively, to anion interstitials. For high concentrations of cation vacancies, the conduction below 100°C is predominantly by electrons in a narrow band at the acceptor level, the activation energy of this “hopping” process being 0.36 eV. The difference between the two acceptor levels is briefly discussed in terms of ligand field splitting of the Cu 3d orbitals.
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    Catalytic activity and selectivity of NaOH-doped γ-aluminas: Dehydration and dehydrogenation of 3-pentanol
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1972, 68 (4), 1972) Chuang, T. T.; Lana, I. G. Dalla
    The catalytic activity of the γ-alumina surface has been investigated using infra-red spectroscopy and interpreted in terms of strong and weak Brønsted-acid sites and Lewis-acid sites. Doping of the γ-alumina with NaOH was used to eliminate Brønsted-acid sites. The influence of the two types of sites upon catalytic activity and selectivity was shown with studies of the simultaneous dehydration and dehydrogenation of 3-pentanol on pure γ-alumina or on several doped aluminas of varying NaOH content. Although the fractional activity of the weak Brønsted-acid sites is greater than that for the Lewis-acid sites, the differences in catalytic behaviour are considerably larger and are attributed to reduced accessibility of the Lewis-acid sites. The selectivity exhibited towards the two reactions was shifted from dehydration to dehydrogenation by eliminating Brønsted-acid sites.
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    Infrared Spectra and Catalytic Activity of Supported Molybdenum Hexacarbonyl
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1972, 68 (12), 1972) Howe, R. F.; Davidson, D. E.; Whan, D. A.
    Infrared spectroscopy has been used to study the olefin disproportionation catalysts consisting of molybdenum hexacarbonyl supported on silica, alumina and magnesia. Activation of the catalysts is found to cause decomposition of the molybdenum hexacarbonyl. Decomposition occurs most readily on a silica support which is not able to stabilize intermediate sub-carbonyl species. The intermediate sub-carbonyl species observed on alumina and magnesia supports arc not active centres for olefin disproportionation ; the active species is formed by complete loss of all six carbonyl ligands. Indirect evidence suggests the active species is not molybdenum(O) but some higher oxidation state.
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    Catalytic Activity and Electron Configuration of the EDA Complexes of Phthalocyanine with Alkali Metals: Hydrogen Adsorption and the H2—D2 Exchange Reaction
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1972, 68 (8), 1972) Naito, Shuichi; Ichikawa, Masaru
    Hydrogen adsorption and H2—D2 exchange reaction on the stoichiometric EDA (electron donor-acceptor) complexes of various phthalocyanines with alkali metals (Li, Na, K, Rb) were studied and their behaviour correlated with the electronic structure of the complexes. It was demonstrated that the activity of the complexes for the HZ—D2 exchange reaction, D2+ HZ ⇌ HD + DZ, where HZ represents the EDA complexes of phthalocyanine, was only dependent upon the number of electrons donated to the π-conjugated system of the ligand, irrespective of the kind of central metal ion. On the other hand, the H2—D2 exchange reaction was markedly affected by the central metal cations, which suggests that the hydrogen dissociation takes place within the crystal field of the metal ions The effect of preadsorbed carbon monoxide on the hydrogen chemisorption and the exchange reaction was also studied, and from these results, the nature of the reaction sites discussed.