Bromine and Iodine Adsorption on an Fe ( 100 ) Surface
نویسنده
چکیده
We studied bromine and iodine adsorption on an Fe(100) surface in the temperature range of 110 K to 700 K. In this communication we compare core-level binding energies of dissociatively and molecularly adsorbed halogen species as a function of coverage. Our valence band photoemission data suggest that bromine and iodine adsorption at 300 K is always dissociative. At 110 K, initial dissociative adsorption is followed by condensation of molecular halogens. At 300 K the core-level binding energies EK of bromine and iodine decrease as a function of coverage by 0.2 eV and 0.7 eV, respectively. The H~ values found for the condensed molecular species are identical to or even lower by 0.3 eV than for the room temperature saturated bromine and iodine overlayers, respectively.
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