https://www.bc.edu/content/dam/files/schools/cas_sites/physics/pdf/Ren/p85.pdf

Advances in the science and technology of carbon nanotubes and their composites: a review

Nanotubes from Carbon.

Bond-orientational order in molecular-dynamics simulations of supercooled liquids and in models of metallic glasses is studied. Quadratic and third-order invariants formed from bond spherical harmonics allow quantitative measures of cluster symmetries in these systems. A state with short-range translational order, but extended correlations in the orientations of particle clusters, starts to develop about 10% below the equilibrium melting temperature in a supercooled Lennard-Jones liquid. The order is predominantly icosahedral, although there is also a cubic component which we attribute to the periodic boundary conditions. Results are obtained for liquids cooled in an icosahedral pair potential as well. Only a modest amount of orientational order appears in a relaxed Finney dense-random-packing model. In contrast, we find essentially perfect icosahedral bond correlations in alternative "amorphon" cluster models of glass structure.

Bond-orientational order in liquids and glasses

Carbon nanotubes can be thought of as graphitic sheets with a hexagonal lattice that have been wrapped up into a seamless cylinder. Since their discovery in 19911, the peculiar electronic properties of these structures have attracted much attention. Their electronic conductivity, for example, has been predicted2,3,4 to depend sensitively on tube diameter and wrapping angle (a measure of the helicity of the tube lattice), with only slight differences in these parameters causing a shift from a metallic to a semiconducting state. In other words, similarly shaped molecules consisting of only one element (carbon) may have very different electronic behaviour. Although the electronic properties of multi-walled and single-walled nanotubes5,6,7,8,9,10,11,12 have been probed experimentally, it has not yet been possible to relate these observations to the corresponding structure. Here we present the results of scanning tunnelling microscopy and spectroscopy on individual single-walled nanotubes from which atomically resolved images allow us to examine electronic properties as afunction of tube diameter and wrapping angle. We observe bothmetallic and semiconducting carbon nanotubes and find thatthe electronic properties indeed depend sensitively on thewrapping angle. The bandgaps of both tube types are consistent with theoretical predictions. We also observe van Hove singularities at the onset of one-dimensional energy bands, confirming the strongly one-dimensional nature of conduction within nanotubes.

Electronic structure of atomically resolved carbon nanotubes

Carbon nanotubes1 are predicted to be metallic or semiconducting depending on their diameter and the helicity of the arrangement of graphitic rings in their walls2,3,4,5. Scanning tunnelling microscopy (STM) offers the potential to probe this prediction, as it can resolve simultaneously both atomic structure and the electronic density of states. Previous STM studies of multi-walled nanotubes6,7,8,9 and single-walled nanotubes (SWNTs)10 have provided indications of differing structures and diameter-dependent electronic properties, but have not revealed any explicit relationship between structure and electronic properties. Here we report STM measurements of the atomic structure and electronic properties of SWNTs. We are able to resolve the hexagonal-ring structure of the walls, and show that the electronic properties do indeed depend on diameter and helicity. We find that the SWNT samples exhibit many different structures, with no one species dominating.

Atomic structure and electronic properties of single-walled carbon nanotubes

The existence of magic numbers for atomic microclusters has been found experimentally for the first time. The magic numbers ${n}^{*}$ manifest themselves in the mass spectra of free xenon clusters, nucleated in the gas phase. The observed numbers ${n}^{*}=13, 55, \mathrm{and} 147$ coincide with the numbers of spheres required for complete-shell icosahedra. The appearance of further magic numbers (19, 25, 71, and 87) is only partially explained by previous calculations.

Magic Numbers for Sphere Packings: Experimental Verification in Free Xenon Clusters

ZnS nanoparticles were prepared by chemical precipitation of Zn2+ with sulfur ions in aqueous solution. The ultraviolet-excited samples reveal detailed structure in the luminescence spectra. A doublet pattern observed in the long wavelength region is attributed to the coexistence of the two crystalline forms in ZnS particles. The visible luminescent radiation at 590.1 nm is due to Mn impurities. The dominant emission band at short wavelengths exhibits a quadruple fine structure with peaks located at 416.1, 423.9, 430.1, and 437.8 nm which are identified with optical transitions arising from vacancy and interstitial sites for both Zn and S atoms.

Luminescence studies of localized gap states in colloidal ZnS nanocrystals

Observation of fullerene cones

The main problems underlying the experimental study of particles with sizes between single atoms and the solid state have been solved: the formation of metal clusters, their individual detection, and the separation of beams with uniform cluster size. By inertgas condensation of metal vapors the clusters ${\mathrm{Sb}}_{1}$-${\mathrm{Sb}}_{500}$, ${\mathrm{Bi}}_{1}$-${\mathrm{Bi}}_{280}$, and ${\mathrm{Pb}}_{1}$-${\mathrm{Pb}}_{400}$ have been produced. The high intensity observed over the whole mass range henceforth allows a systematic size-dependent investigation of metal clusters.

Generation of Metal Clusters Containing from 2 to 500 Atoms

Design and Theory The Quantum Nature of Nanoscience, Marvin L. Cohen Theories for Nanomaterials to Realize a Sustainable Future, Rodion V. Belosludov, Natarajan S. Venkataramanan, Hiroshi Mizuseki, Oleg S. Subbotin, Ryoji Sahara, Vladimir R. Belosludov, and Yoshiyuki Kawazoe Tools for Predicting the Properties of Nanomaterials, James R. Chelikowsky Design of Nanomaterials by Computer Simulations, Vijay Kumar Predicting Nanocluster Structures, John D. Head Nanoscale Systems The Nanoscale Free-Electron Model, Daniel F. Urban, Jerome Burki, Charles A. Stafford, and Hermann Grabert Small-Scale Nonequilibrium Systems, Peder C.F. Moller and Lene B. Oddershede Nanoionics, Joachim Maier Nanoscale Superconductivity, Francois M. Peeters, Arkady A. Shanenko, and Mihail D. Croitoru One-Dimensional Quantum Liquids, Kurt Schonhammer Nanofluidics of Thin Liquid Films, Markus Rauscher and Siegfried Dietrich Capillary Condensation in Confined Media, Elisabeth Charlaix and Matteo Ciccotti Dynamics at the Nanoscale, A. Marshall Stoneham and Jacob L. Gavartin Electrochemistry and Nanophysics, Werner Schindler Thermodynamics Nanothermodynamics, Vladimir Garcia-Morales, Javier Cervera, and Jose A. Manzanares Statistical Mechanics in Nanophysics, Jurij Avsec, Greg F. Naterer, and Milan Marcic Phonons in Nanoscale Objects, Arnaud Devos Melting of Finite-Sized Systems, Dilip Govind Kanhere and Sajeev Chacko Melting Point of Nanomaterials, Pierre Letellier, Alain Mayaffre, and Mireille Turmine Phase Changes of Nanosystems, R. Stephen Berry Thermodynamic Phase Stabilities of Nanocarbon, Qing Jiang and Shuang Li Nanomechanics Computational Nanomechanics, Wing Kam Liu, Eduard G. Karpov, and Yaling Liu Nanomechanical Properties of the Elements, Nicola M. Pugno Mechanical Models for Nanomaterials, Igor A. Guz, Jeremiah J. Rushchitsky, and Alexander N. Guz Nanomagnetism and Spins Nanomagnetism in Otherwise Nonmagnetic Materials, Tatiana Makarova Laterally Confined Magnetic Nanometric Structures, Sergio Valeri, Alessandro di Bona, and Gian Carlo Gazzadi Nanoscale Dynamics in Magnetism, Yves Acremann and Hans Christoph Siegmann Spins in Organic Semiconductor Nanostructures, Sandipan Pramanik, Bhargava Kanchibotla, and Supriyo Bandyopadhyay Nanoscale Methods Nanometrology, Stergios Logothetidis Aerosol Methods for Nanoparticle Synthesis and Characterization, Andreas Schmidt-Ott Tomography of Nanostructures, Gunter Mobus and Zineb Saghi Local Probes: Pushing the Limits of Detection and Interaction, Adam Z. Stieg and James K. Gimzewski Quantitative Dynamic Atomic Force Microscopy, Robert W. Stark and Martin Stark STM-Based Techniques Combined with Optics, Hidemi Shigekawa, Osamu Takeuchi, Yasuhiko Terada, and Shoji Yoshida Contact Experiments with a Scanning Tunneling Microscope, Jorg Kroger Fundamental Process of Near-Field Interaction, Hirokazu Hori and Tetsuya Inoue Near-Field Photopolymerization and Photoisomerization, Renaud Bachelot, Jerome Plain, and Olivier Soppera Soft X-Ray Holography for Nanostructure Imaging, Andreas Scherz Single-Biomolecule Imaging, Tsumoru Shintake Amplified Single-Molecule Detection, Ida Grundberg, Irene Weibrecht, and Ulf Landegren Index

Klaus Sattler

Papers

Magic Numbers for Sphere Packings: Experimental Verification in Free Xenon Clusters

Luminescence studies of localized gap states in colloidal ZnS nanocrystals

Observation of fullerene cones

Generation of Metal Clusters Containing from 2 to 500 Atoms

Principles and methods