Transformations of molecular structures formed by perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) molecules on a rutile TiO2(110) surface are studied with low-temperature scanning tunnelling microscopy. We demonstrate that metastable molecular assemblies transform into differently ordered structures either due to additional energy provided by thermal annealing or when the influence of int...

Scanning tunnelling microscopy (STM) has been used to investigate the formation of hydrogen-bonded structures of the isophthalate tetracarboxylic acids, biphenyl-3,3',5,5'-tetracarboxylic acid (BPTC), terphenyl-3,3″,5,5″-tetracarboxylic acid (TPTC), and quarterphenyl-3,3‴,5,5‴-tetracarboxylic acid (QPTC), via deposition from solution onto Au(111). STM data reveal that ordered structures can be ...

We have performed a high-resolution synchrotron radiation photoelectron spectroscopy study of the initial growth stages of the ZnPd near-surface alloy on Pd(111), complemented by scanning tunnelling microscopy data. We show that the chemical environment for surfaces containing less than half of one monolayer of Zn is chemically distinct from subsequent layers. Surfaces where the deposition is p...

We present a theory of the pinning of dynamic spin-density-wave ~SDW! fluctuations in a d-wave superconductor by local imperfections that preserve spin-rotation invariance, such as impurities or vortex cores. The pinning leads to static spatial modulations in spin-singlet observables, while the SDW correlations remain dynamic: these are the ‘‘Friedel oscillations’’ of a spin-gap antiferromagnet...

Physical vapour deposition of ZnO on an Au(111) support has been investigated as a function of the oxygen chemical potential by means of scanning tunnelling microscopy and luminescence spectroscopy. Whereas a layer-by-layer growth of ZnO is revealed in oxygen excess, formation of oxide nanorods with large height-to-diameter ratio prevails at lower oxygen chemical potentials. We ascribe the form...

We present a theory of the pinning of dynamic spin density wave (SDW) fluctuations in a d-wave superconductor by local imperfections which preserve spin-rotation invariance, such as impurities or vortex cores. The pinning leads to static spatial modulations in spin-singlet observables, while the SDW correlations remain dynamic: these are the ‘Friedel oscillations’ of a spin-gap antiferromagnet....

Scanning tunnelling microscopy (STM) and X-ray photoelectron spectroscopy (XPS, AES) were used to study MOCVD of Cu-clusters on the mixed terminated ZnO(10% 10) surface in comparison to MBE Cu-deposition. Both deposition methods result in the same Cu cluster morphology. After annealing to 670 K the amount of Cu visible above the oxide surface is found to decrease substantially, indicating a sub...

Guided by scanning tunnelling microscopy images of regularly stepped surfaces it will be illustrated that there is a striking similarity between the behaviour of monoatomic step edges and quantum mechanical particles (spinless fermions). The direction along the step edge is equivalent to the time, while the direction perpendicular to the step corresponds to the one-dimensional space along which...

The formation of atomically precise covalent networks directly on a surface is a promising approach to produce single layers of two-dimensional organic materials (2D polymers). In the emerging field of on-surface synthesis, there is an urgent need for finding a rationale to new reaction pathways taking place directly on the surface. In this feature article we review and put into perspective rec...

Scanning tunnelling microscopy (STM) has been performed in air at room temperature on bilayers of the nucleic acid base adenine, adsorbed to a graphite surface following evaporation of saturated aqueous solutions. Our results indicate that the upper layer of the bilayer structure shows a structural change compared to the layer adsorbed directly to the graphite. The upper layer has a slightly la...