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A comparative analysis between a solution and a surface-mediated synthesis of heterotriangulene macrocycles is reported. The results show a preferential formation of the πconjugated macrocycles on surface due to two-dimensional confinement. The macrocycle prepared on a several hundred milligram scale by solution chemistry was characterized by single-crystal X-ray analysis and was furthermore extended toward next generation honeycomb species. Investigation of the photophysical and electronic properties together with the good thermal stability revealed the potential of MC6 as hole-transport material for organic electronics.

Tunneling electrons from a scanning tunneling microscope (STM) induce luminescence from C(60) and C(70) molecules forming fullerene nanocrystals grown on ultrathin NaCl films on Au(111). Intramolecular fluorescence and phosphorescence associated with the transitions between the lowest electronic excited state and ground state of C(70) molecules are identified, leading to unambiguous chemical recognition on the nanoscale. Moreover we demonstrate that the molecular luminescence is selectively enhanced by localized surface plasmons in the STM tip-sample gap.

We report on the surface-catalyzed formal [2+2] and [2+2+2] cycloadditions of ortho-activated tetracene species on a Ag(111) substrate under ultrahigh vacuum conditions. Three different products are obtained: tetracene dimers, trimers, and tetramers. The former results from the formation of a four-membered ring while the other two arise from cyclization into six-membered rings. These on-surface reactions have been monitored by scanning tunneling microscopy and rationalized by density functional theory calculations. Our approach, based on the reaction of ortho-dihalo precursor monomers via formal cycloadditions, establishes an additional method for the highly active field of on-surface synthesis and enables the development of novel 1D and 2D covalent carbon nanostructures.

The growth of fullerene nanocrystals, composed of only C(60), only C(70), or a mixture of both fullerenes, has been investigated by scanning tunneling microscopy (STM). The nanocrystals, formed on a NaCl ultrathin layer partially covering a Au(111) surface, have characteristic truncated-triangular or hexagonal shapes, with lateral size up to 100 nm and a typical height of two to four molecular layers. This growth mode differs considerably from the ones observed on metallic surfaces. STM images with biasdependent submolecular resolution reveal the spatial distribution of the electronic density originating from the molecular orbitals. A comparison of the experimental results with first-principles density functional theory calculations allows us to unambiguously determine the orientation and the nature of individual fullerene molecules in the surface layer of the nanocrystals. Growth and characterization of fullerene nanocrystals on NaCl/Au(111) The growth of fullerene nanocrystals, composed of only C60, only C70, or of a mixture of both fullerenes, has been investigated by Scanning Tunneling Microscopy (STM). The nanocrystals, formed on a NaCl ultrathin layer partially covering a Au(111) surface, have characteristic truncatedtriangular or hexagonal shapes, with lateral size up to 100 nm and a typical height of two to four molecular layers. This growth mode differs considerably from the ones observed on metallic surfaces. STM images with bias-dependent submolecular resolution reveal the spatial distribution of the electronic density originating from the molecular orbitals. A comparison of the experimental results with first principle Density Functional Theory (DFT) calculations allows us to unambiguously determine the orientation and the nature of individual fullerene molecules in the surface layer of the nanocrystals.

Experimental results from equimolar PEG and protein standards samples are presented from a MALDI-TOF mass spectrometer equipped with both ionizing detectors and the novel single molecule sensitive cryodetectors. The data are consistent with a model hypothesis suggesting that the observed decrease in signal strength in conventional ionizing detector MALDI-TOF mass spectrometers can be explained by the exponentially decreasing quantum efficiency of ionizing detectors. Cryodetectors, in contrast, have a mass independent detection efficiency of 100% on impact and provide additional information on the molecule state owing to the calorimetric nature of the detection mechanism.

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