CHEMISORPTION OF NITROGEN ON CU(110) - COVERAGE AND SITE DETERMINATION

Chemisorption of nitrogen on Cu(110) has been studied using XPS, LEED, AES, and TDS. Gas phase nitrogen was activated and accelerated to 200 eV to promote interaction with the surface. Coverages were obtained from XPS N 1s areas and calibrated using a p(2 × 1)O structure. After exposures at 300 K, nitrogen coverages saturated near 1 ML. The width of the N 1s core indicates that only one site is occupied for coverages below 2 3 ML, but additional site(s) are occupied at higher coverages. Annealing the crystal to 650 K produced a stable (2 × 3) structure consisting of 2 3 ML of nitrogen in a single site. The lineshape of the nitrogen Auger signal is independent of coverage or surface structure. Annealing the crystal to 800 K removes all nitrogen from the surface, by a combination of desorption and absorption into the bulk. © 1990.