Using the highly localized current of electrons tunneling through a double barrier Scanning Tunneling Microscope (STM) junction, we excite luminescence from a selected C60 molecule in the surface layer of fullerene nanocrystals grown on an ultrathin NaCl film on Au(111). In the observed luminescence fluorescence and phosphorescence spectra, pure electronic as well as vibronically induced transitions of an individual C60 molecule are identified, leading to unambiguous chemical recognition on the single-molecular scale.PACS numbers: 68.37. Ef, 73.20.Mf, Light emission induced by electrons tunneling through the junction formed by the sample and the tip of a Scanning Tunneling Microscope (STM) has been proposed to characterize the optical properties of nanoscale objects at surfaces [1]. Contrary to conventional non-local techniques, the local character of this method offers the unique possibility to select and probe individual atoms, molecules or clusters on surfaces.Photon emission due to the decay of localized surface plasmons, excited by inelastic electron tunneling (IET) has been observed on metal surfaces [2,3], as well as on supported metallic nanoparticles [4]. Luminescence spectra have been acquired from semiconductor heterostructures [5], quantum well states of metallic films [6]. Recently, luminescence from supported molecules has been obtained [7,8] by successfully decoupling them from the metallic substrate in order to avoid quenching of the radiative transitions [9,10], using either a thin oxide film [7] or several molecular layers [8].However, unambiguous chemical identification of single complex molecules requires the observation and identification of several vibrational and/or electronicvibrational transitions, which are the spectroscopic fingerprint of the species. Here we present the first observation of energy resolved luminescence from an individually selected C 60 molecule excited by electrons tunneling through a double barrier STM junction. A comparison with the luminescence spectra obtained by non-local laser spectroscopy from dispersed C 60 molecules in rare gas and glass matrices [11,12,13,14,15,16], and from solid C 60 [17,18,19] enables us to demonstrate the molecular origin of the detected light and to identify the observed spectral features with pure electronic transitions and with vibronic transitions induced via Jahn-Teller (JT) and Herzberg-Teller (HT) coupling [20,21]. The present novel observation of both, fluorescence (singletto-singlet transitions) and phosphorescence (triplet-tosinglet transitions) constitutes a solid basis for the chemical identification of an individual C 60 molecule.C 60 nanocrystals were grown on NaCl layers deposited onto a Au(111) substrate. NaCl was evaporated from a Knudsen cell on a clean Au(111) surface at room temperature. Subsequently, the C 60 molecules were sublimated on the NaCl covered substrate. The experiments were performed with a homebuilt ultrahigh vacuum (UHV) STM operating at a temperature of 50 K, using cut PtIr tips. The photons emitted f...

Nested assembly: Chiral molecules of 5,6,11,12‐tetraphenylnaphthacene (rubrene) organize spontaneously into homochiral supramolecular architectures of increasing complexity. Adsorbed individual molecules self‐assemble enantioselectively into chiral pentagonal supermolecules, which act as building blocks for the formation of chiral supramolecular decagons (see STM images).

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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.