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Adsorption of fullerene and azafullerene on Cu(111) studied by electron energy loss spectroscopy

Fullerene and azafullerene films were studied by electron energy loss spectroscopy in reflection geometry. Compared to C60, (C59N)2 multilayers show additional vibrational modes that are characteristic of the dimer structure. The (C59N)2 is semiconductor-like and giant optically allowed excitonic transitions are found in the gap in drastic contrast with C60. The azafullerene monolayer on Cu(111) no longer shows the presence of dimers, indicating monomer adsorption. Similarly to C60, azafullerene molecules in contact with the metal substrate receive a transferred charge between two and three electrons. However, the C59N appears more covalently bound to Cu because it decomposes when heated above 660 K while C60 only desorbs.

Smart hybrid nanostructures for cancer treatment

The project leading to this work has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 751903

Chemical imaging of single 4,7,12,15-tetrakis †2.2 ‡paracyclophane by spatially resolved vibrational spectroscopy

Single 4,7,12,15-tetrakis͓2.2͔paracyclophane were deposited on NiAl͑110͒ surface at 11 K. Two adsorbed species with large and small conductivities were detected by the scanning tunneling microscope ͑STM͒. Their vibrational properties were investigated by inelastic electron tunneling spectroscopy ͑IETS͒ with the STM. Five vibrational modes were observed for the species with the larger conductivity. The spatially resolved vibrational images for the modes show striking differences, depending on the coupling of the vibrations localized on different functional groups within the molecule to the electronic states of the molecule. The vibrational modes are assigned on the basis of ab initio calculations. No IETS signal is resolved from the species with the small conductivity

Two-Dimensional 1,3,5-Tris(4-carboxyphenyl)benzene Self-Assembly at the 1-Phenyloctane/Graphite Interface Revisited

International audienceTwo-dimensional (2D) self-assembly of star-shaped 1,3,5-tris(4-carboxyphenyl)benzene molecules is investigated. Scanning tunneling microscopy reveals that this molecule can form three hydrogen-bonded networks at the 1-phenyloctane/graphite interface. One of these structures is close-packed and the two other ones are porous structures, with hexagonal and rectangular cavities. The network with rectangular cavities appears to be the most stable structure

Converse Piezoelectricity and Ferroelectricity in Crystals of Lysozyme Protein Revealed by Piezoresponse Force Microscopy

In recent years, piezoresponse force microscopy (PFM) has been used to investigate the piezoelectric and ferroelectric behaviour of many biological materials. Piezoelectricity has been studied in fibrous proteins such as collagen [1, 2] and elastin [3], with the later also demonstrating ferroelectricity. However, a comprehensive understanding of piezoelectricity and ferroelectricity in non-fibrous proteins is lacking.Acknowledgement: Funding from the Irish Research Council Embark Postgraduate Scholarship (2012-2015) is acknowledged. CICECO and FCT are acknowledged via grant PestC/CTM/LA0011/013

Multimodal characterization of broadband, polycrystalline silver halide fibre bundle for confocal laser scanning microscopy in the near-mid infrared spectra

This work was supported by the Russian Science Foundation under grant No. 18-73-11063

Piezoresponse force microscopy and electron backscattering diffraction of 90° ferroelectric twins in BaTiO3 positive temperature coefficient (PTC) thermistors

The authors acknowledge funding from the European Union's Horizon 2020 research and innovation program, OYSTER (Open characterisation and modelling environment to drive innovation in advanced nanoarchitectured and bio-inspired hard/soft interfaces) under grant agreement No 760827, Enterprise Ireland, Innovation Partnership Programme (Project No: IP/2013/0281), Irish Research Council postgraduate scholarship and Higher Education Authority (HEA)