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The structure and bonding of acetone on Cu(1 1 1) has been probed using a combination of temperature programmed desorption, UV photoelectron spectroscopy (UPS) and normal incidence X-ray standing wavefield absorption (NIXSW). Acetone was found to interact very weakly with Cu(1 1 1). This is evidenced by UPS data, which showed no significant perturbation of the electronic structure of acetone upon adsorption. NIXSW data is consistent with acetone adsorbing to the surface via the oxygen with an atop local registry in a η1(O) configuration. The observed Cu–O distance of 2.73 ± 0.16 Å is close to the expected van der Waals separation (2.93 Å). The local registry determined in the present study is consistent with that predicted in previous theoretical work. [Copyright &y& Elsevier]

Normal incidence X-ray standing wavefield absorption (NIXSW) and temperature programmed desorption (TPD) have been used to study the bonding of both furan and tetrahydrofuran (THF) on Cu(1 1 1). THF was found to adopt an atop adsorption site, with furan adopting a displaced atop position. We attribute this displacement to the effects of adsorbate–adsorbate interactions, the magnitude of which are significant compared to the strength of the furan to copper interaction. The adsorption of THF is significantly stronger than that of furan, which we propose is due to the influence of C–H⋯Cu interactions between THF and the copper surface. [Copyright &y& Elsevier]

The local registry of methoxy and methanol adsorbed on Cu(1 1 1) has been studied using normal incidence X-ray standing wavefield absorption (NIXSW). Methanol adsorbs to the surface with its oxygen atom directly above a Cu atom, with a Cu–O separation of 2.69 ± 0.19 A˚. This distance is only slightly shorter than that expected for a purely van der Waals interaction (2.96 A˚), which indicates that the molecule is only weakly chemisorbed to the surface. In contrast to methanol, methoxy is strongly chemisorbed on Cu(1 1 1). The NIXSW data can be modelled assuming methoxy adopts threefold hollow adsorption sites, in agreement with other studies. The NIXSW data is consistent with methoxy populating both FCC and HCP hollow sites, this contradicts previous work which suggests that the species only occupies FCC type hollows. The results of our studies have been compared with previous theoretical predictions for the structure of methanol and methoxy on Cu(1 1 1), and differences between experiment and theory have been highlighted. [Copyright &y& Elsevier]

The structure of a disordered chemisorbed oxygen layer on Cu(1 1 1) has been investigated using normal incidence X-ray standing wavefield absorption (NIXSW). The NIXSW data indicates that the oxygen atoms within the overlayer have more than one well-defined height with respect to the copper surface. The NIXSW data has been compared to previous proposed structural models for the disordered overlayer. We believe that the model that is most consistent with our data is the oxygen overlayer having a Cu2O-like structure. [Copyright &y& Elsevier]