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A dihydro-TTF derivative with four acetyl-protected thiol ligands was synthesised and adsorbed on Au(111) under UHV conditions. Scanning Tunnelling Microscopy (STM) and Infrared (IR) spectroscopy show that self-organised structures are formed following annealing to 333 K, with each pair of bidentate thiolate ligands bonding to a single gold adatom in a S-Auad-S complex. Due to the lack of a direct orbital overlap between the dihydro-TTF moieties and the surface, relatively little charge transfer between TAT-TTF and the gold surface occurs.

Driven by the demand for heterogeneous asymmetry catalysis, studies of chiral surfaces have become important aspects of modern surface science. With the maturity of surface science techniques, this has enriched the success in the study of low-symmetry chiral surfaces at the molecular level. In this review we summarise the methods to create chiral surfaces and the symmetry properties of chiral surfaces. Physical methods that have been used to recognise and understand the structure and properties of chiral surfaces are discussed in detail.

The hydrogenation of but-2-enal over supported Au catalysts is discussed, together with a detailed characterisation study using X-ray diffraction, infrared spectroscopy and transmission electron microscopy. Au/ZnO catalysts are found to be selective for the formation of the unsaturated alcohol, but-2-en-1-ol rather than the saturated aldehyde, butanal. In general, the addition of thiophene is found to enhance the yield of the unsaturated alcohol. Detailed transmission electron microscopy and infrared spectroscopy studies show that thiophene modification of Au/ZnO catalysts does not affect the Au-particle size or morphology; rather, thiophene undergoes irreversible dissociative adsorption giving a surface in which the Au sites are electronically promoted by sulfur. It is observed that thiophene modification does not give any marked effect on catalyst performance for the catalysts that contain large Au-particles (10 nm) and, hence, it is considered that the sulfur promotion observed is associated with smaller Au nanoparticles. The highest but-2-en-1-ol selectivities (∽80%) are observed for 5 wt.% Au/ZnO catalysts reduced at 400°C prior to reaction. It is proposed that the origin of high selectivity is associated with large Au particles (10–20 nm in diameter) that are present in this catalyst.

The hydrogenation of crotonaldehyde over Cu/Al2O3 which was modified by formic acid or acetic acid adsorption has been investigated, exposed Cu sites being characterised using infrared spectroscopy with CO as a probe molecule. Formic acid adsorption on reduced Cu0 sites generated adsorbed bidentate formate which blocked CO adsorption at many sites, induced cationic character at the remaining available sites, and partially poisoned hydrogenation reactions. Modification of the surface poisoned CO hydrogenation more than CC hydrogenation and hence promoted butanal as the dominant hydrogenation product. Desorption of formate by “ flashing” at high temperature resulted in a partly reconstructed surface which gave higher catalytic activities than an unmodified surface before formic acid treatment. However, crotyl alcohol remained a minor product. The effects of acetic acid adsorption were similar to those for formic acid except that attempts at desorption of the modifier resulted in carbonaceous residues which partially poisoned both CO adsorption and catalytic activity.

Benzotriazole (BTAH) has been used as a copper corrosion inhibitor since the 1950s; however, the molecular level detail of how inhibition occurs remains a matter of debate. The onset of BTAH adsorption on a Cu(111) single crystal was investigated via scanning tunnelling microscopy (STM), vibrational spectroscopy (RAIRS) and supporting DFT modelling. BTAH adsorbs as anionic (BTA(-)), CuBTA is a minority species, while Cu(BTA)2, the majority of the adsorbed species, form chains, whose sections appear to diffuse in a concerted manner. The copper surface appears to reconstruct in a (2 × 1) fashion.

The tri-para-carboxylic polychlorotriphenylmethyl radical adsorption on a Cu/Au(111) surface has been investigated in ultra-high vacuum environment. The presence of copper favours the formation of metal-organic assemblies, which are analysed using scanning tunnelling microscopy (STM) and high resolution electron energy loss spectroscopy (HREELS). DFT methods indicate that the unpaired electron survives after adsorption, thus creating systems which could be regarded as potential candidates for spintronics applications.

Both R- and S-phenylglycine and a quantitatively well defined mixture of the two enantiomers have been studied on Cu{110} surfaces. At saturation coverage, the molecules form well ordered, chiral structures with a chiral unit cell which ensures that the LEED patterns of the two enantiomers are readily differentiated. Comparison is made with analogous structures observed for the non-chiral species glycine and R-, S-alanine adsorbed on Cu{110}.

The adsorption of formic acid on Cu(110) has been studied using Fourier-transform reflection/absorption IR spectroscopy (FTRAIRS) and molecular beam measurements. The adsorption is inefficient at 300 K, having an initial sticking coefficient (S0) of ca. 0.1. Experiments with sub-ambient crystal temperatures show much more efficient adsorption with S0 being 0.9 at 180 K. The absorption appears to be of the precursor type. FTRAIRS indicates that the species adsorbed at 200 K is very different from that at 300 K. The latter is the usually reported bidentate formate with a simple IR spectrum and symmetrically equivalent oxygens. At 200 K we propose that formate is produced in the monodentate form, that is strongly anchored to the surface through one oxygen, with the other in the form of a carbonyl group. However, the carbonyl group may also be bonding to the surface weakly. The monodentate species converts to bidentate upon heating. If the bidentate formate is cooled to 200 K, formic acid can be adsorbed from the gas phase and this converts all the formate on the surface back to the monodentate form.

Real-time reflectance anisotropy (RA) transients have been recorded from a cu(110) surface during exposure to O2, O2–HCO2H and C6H5CO2H, using a simple HeNe laser-based system operating at 1.96 eV polarised parallel to first the [110] and then the [100] directions on the crystal surface. The marked changes in the RA response observed during the formation of the reconstructed overlayers is attributed to the quenching of an allowed optical transition of the surface, as identified using electron spectroscopy, by the process of adsorption and restructuring. However, the influence of new adsorbate-induced states on the RA response cannot be ruled out at present. The magnitude of the observed changes in RA are comparable for the formation of the p(2 × 1)O and (3 × 1)O/HCO2H structures and are tentatively assigned to a combination of the rapid quenching of an allowed surface transition and the possible modification of new adsorbate-induced states. For the formation of the c(8 × 2) benzoate overlayer the RA change is considerably larger, which is believed to be due to a more thorough quenching of the allowed surface transition than that which occurs for the other systems studied. For the formation of the initial stages of the (2 × 1)O overlayer, in particular, the RA response would be consistent with simple Langmuir adsorption kinetics providing that a model in which the RA response was directly proportional to coverage was applicable.

Photoelectron spectra excited in the gas phase with He-I radiation are reported for the tetroxides, RuO4 and OsO4, and for the oxychloride species VOCl3, CrO2Cl2 and MoO2Cl2. The X-ray photoelectron spectrum of OsO4 has also been measured. The nature of the metal-oxygen bonding in these molecules, as inferred from the spectrometric data, is discussed.

Structure, close to the Fermi level, in the u.v. photoemission spectrum of the (111) face of a copper single crystal is investigated as a function of emission angle, photon incidence angle and photon energy. The structure is assigned to surface state emission because of its sensitivity to the presence of adsorbed mercury.

The usefulness of certain molecular orbital theories in the prediction of molecular ionization energies is investigated. A simple Huckel treatment offers definite advantages over the more imposing CNDO method. The ab initio FSGO method of Frost is unreliable quantitatively.