Room - Temperature Chemistry of Acetylene on Pd ( 11 1 ) : Formation of Vinylidene
نویسنده
چکیده
The surface species formed following acetylene adsorption on Pd( 1 1 1) a t 300 K is identified as a vinylidene. It is oriented with its carbon+arbon axis tilted at -50’ to the surface normal which allows overlap between molecular ‘lr orbitals and the surface d-orbitals. The carbon4arbon bond is slightly longer (by -0.03 A) than for adsorbed ethylene on Pd( 1 1 1). This assignment is consistent with previous photoelectron and high-resolution electron energy loss spectroscopy data. Adsorbed vinylidene decomposes to yield hydrogen and deposit carbon onto the surface at -480 K with an activation energy of 11 5 kJ/mol.
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تاریخ انتشار 2001