The effect of lateral interactions on the thermal desorption of N₂ from Ni(100)

We have investigated the desorption of N₂ from Ni(100) using thermal desorption spectroscopy (TDS). A modified Polanyi–Wigner equation has been used to obtain the desorption energy and the preexponential factor, both of which depend on the coverage of the adsorbate. We show that there is a large lateral interaction among the adlayer molecules when N₂ goes down as ordered c(2×2) on Ni. In addition, the overlayer ordering, in the thermal desorption process, is observed to affect the thermal desorption spectra.