The ability of scanning tunneling microscopy to manipulate selected C(60) molecules within close packed C(60) arrays on a (Au,In)/Si(111) surface has been examined for mild conditions below the decomposition threshold. It has been found that knockout of the chosen C(60) molecule (i.e., vacancy formation) and shifting of the C(60) molecule to the neighboring vacant site (if available) can be conducted for wide ranges of bias voltages (from -1.5 to +0.5 V), characteristic manipulation currents (from 0.02 to 100 nA) and powers (from 2 × 10(-8) to 0.1 μW). This result implies that the manipulation is not associated with the electrical effects but rather has a purely mechanical origin. The main requirement for successful C(60) knockout has been found to be to ensure a proper 'impact parameter' (deviation from central impact on the C(60) sphere by the tip apex), which should be less than ~1.5 Å. A certain difference has been detected for the manipulation of C(60) in extended molecular arrays and molecular islands of a limited size. While it is possible to manipulate a single C(60) molecule in an array, in the case of a C(60) island it appears difficult to manipulate a given fullerene without affecting the other ones constituting the island.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1088/0957-4484/24/5/055302 | DOI Listing |
Chemphyschem
January 2025
Department of Physics, Yingbin Road 688, Jinhua, CHINA.
Undesirable loss of open-circuit voltage and current of metal halide perovskite (MHP) solar cells are closely associated with defects, so theoretical calculations have been often performed to scrutinize the nature of defects in bulk of MHPs. Yet, exploring the properties of defects at surfaces of MHPs is severely lacking given the complexity of the surface defects with high concentrations. In this study, IPb (PbI) antisite defects, namely one Pb (I) site being occupied by one I (Pb) atom at the surfaces of the FAPbI3 (FA = CH(NH2)2) material, are found to create electron (hole) traps when the surfaces with IPb (PbI) antisite defects are negatively (positively) charged.
View Article and Find Full Text PDFOrg Chem Front
December 2024
Departamento de Química Orgánica I, Facultad de Ciencias Químicas, Universidad Complutense de Madrid Av. Complutense S/N 28040 Madrid Spain
Supramolecular chemistry of carbon-based materials provides a variety of chemical structures with potential applications in materials science and biomedicine. Here, we explore the supramolecular complexation of fullerenes C and C, highlighting the ability of molecular nanographene tweezers to capture these structures. The binding constant for the CNG-1⊃C complex was significantly higher than for CNG-1⊃C, showing a clear selectivity for the more π-extended C.
View Article and Find Full Text PDFChem Sci
December 2024
Materials Innovation Factory, Department of Chemistry, University of Liverpool 51 Oxford Street L7 3NY Liverpool UK
Proc Natl Acad Sci U S A
December 2024
Department of Chemistry, University of Hawai'i at Manoa, Honolulu, HI 96822.
The cyclopentadiene (CH) molecule has emerged as a molecular building block of nonplanar polycyclic aromatic hydrocarbons (PAHs) and carbonaceous nanostructures such as corannulene (CH), nanobowls (CH), and fullerenes (C) in deep space. However, the underlying elementary gas-phase processes synthesizing cyclopentadiene from acyclic hydrocarbon precursors have remained elusive. Here, by merging crossed molecular beam experiments with rate coefficient calculations and comprehensive astrochemical modeling, we afford persuasive testimony on an unconventional low-temperature cyclization pathway to cyclopentadiene from acyclic precursors through the reaction of the simplest diatomic organic radical-methylidyne (CH)-with 1,3-butadiene (CH) representing main route to cyclopentadiene observed in TaurusMolecular Cloud.
View Article and Find Full Text PDFJ Phys Chem A
December 2024
Spectroscopy Division, Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto Sayo, Hyogo 679-5198, Japan.
The C fullerene cage can encapsulate a small molecule like water and provides room to leave the encapsulated component rather isolated, but the true nature of the intracomplex interactions should be further elucidated for better understanding and utility of this series of complexes. Here, an analysis toward this goal is conducted for HO@C by infrared spectral measurements and theoretical calculations. It is shown that the response of the π electrons of the C cage upon encapsulating a water molecule is single-sided and delocalized in that the electron density is partially transferred from the - side to the + side of the cage (when the axis is taken along the water dipole) but almost only inside the cage, explaining the significant reduction of the dipole moment and the infrared intensities.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!