Influence of adsorption geometry in the heterogeneous enantioselective catalytic hydrogenation of a prototypical enone
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چکیده
The Pd(111) crystal was attached to a motorized manipulator using tantalum wires and could be heated by means of electron bombardment to 900 K or cooled to 77 K, as monitored by a T1T2 thermocouple attached directly to the sample. It was cleaned by cycles of Ar sputtering (4 keV, 7 μA) and annealing (850 K) followed by brief heating to ~ 850 K in the presence of 2×10 mbar of O2 to remove residual carbon contamination. Annealing at 800 K in vacuum for 5 minutes resulted in a clean (XPS), atomically flat surface (LEED).
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