Site switching and surface restructuring induced by NO adsorption on Pt{110}

We present the first infrared vibrational study of the adsorption of NO on Pt(110) over a wide range of temperatures. Adsorption is strongly dependent on both temperature and coverage, with many different species being formed on the surface. Under all conditions, site switching is observed during NO adsorption: at low coverages bridge-bonded species are formed on the surface, and at very high coverage NO switches to on-top sites. Other species, not previously reported, are also observed, depending on both adsorption temperature and coverage. The clean Pt(110) surface exhibits a (1 x 2) surface reconstruction which can be lifted by the adsorption of NO (or CO), depending on surface temperature and adsorbate coverage. In contrast to CO adsorption, the on-top surface species shows different frequencies on the(1 x 2) and(1 x 1) surface phases, and this is deployed to identify the temperature at which the reconstruction begins to lift.