A multitechnique approach to weakly chemi-sorbed phases: N2 on Ni{110)

Complete characterization of an adsorbate system requires that many physical and chemical properties be determined from experimental data. Important quantities include: (1) the structure of the adsorbate phases; (2) thermodynamic quantities such as heats and entropies of adsorption and desorption; and (3) kinetic parameters which describe adsorption, desorption and ordering processes in the adsorbate phase. No single experimental technique can provide all of the necessary data over the complete range of coverages and temperatures and several techniques are usually required to minimize experimental ambiguities and artifacts. This review demonstrates the utility of such a multitechnique approach by describing a complete study of the chemisorption of molecular nitrogen of the nickel (110) surface. The techniques used are low-energy electron diffraction (LEED), ion scattering spectroscopy (ISS), infrared reflection absorption spectroscopy (IRRAS), X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), work function change measurements, and thermal desorption spectroscopy (TDS). The data from these experimental studies are correlated and used to test theoretical models. Extensive physical and chemical data for the N2/Ni(110) system are presented and compared with that of other molecular adsorption systems