Adsorption and dissociation of O2 on Ir„111..
نویسندگان
چکیده
The adsorption and dissociation of dioxygen on the Ir~111! surface have been studied using periodic self-consistent density functional theory ~DFT-GGA! calculations. Three di-s-type chemisorbed molecular precursors are identified: One is located over bridge sites and has a binding energy of 21.3 eV and a bond length of 1.4 Å; the other two are located over threefold hollows and have similar binding energies of ca. 21.2 eV and bond lengths of ca. 1.5 Å. None are magnetic, suggesting a peroxo (O2 ) nature for these precursors. The minimum energy path for O2 dissociation is determined using the nudged elastic band method, and a very small activation energy is found, ca. 0.06 eV. © 2002 American Institute of Physics. @DOI: 10.1063/1.1479716#
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