Journal ArticleDOI
Band gap fluorescence from individual single-walled carbon nanotubes.
Michael J. O'Connell,Sergei M. Bachilo,Chad B. Huffman,Valerie C. Moore,Michael S. Strano,Erik H. Haroz,Kristy L. Rialon,Peter J. Boul,William H. Noon,Carter Kittrell,Jianpeng Ma,Jianpeng Ma,Robert H. Hauge,R. Bruce Weisman,Richard E. Smalley +14 more
TLDR
At pH less than 5, the absorption and emission spectra of individual nanotubes show evidence of band gap–selective protonation of the side walls of the tube, which is readily reversed by treatment with base or ultraviolet light.Abstract:
Fluorescence has been observed directly across the band gap of semiconducting carbon nanotubes. We obtained individual nanotubes, each encased in a cylindrical micelle, by ultrasonically agitating an aqueous dispersion of raw single-walled carbon nanotubes in sodium dodecyl sulfate and then centrifuging to remove tube bundles, ropes, and residual catalyst. Aggregation of nanotubes into bundles otherwise quenches the fluorescence through interactions with metallic tubes and substantially broadens the absorption spectra. At pH less than 5, the absorption and emission spectra of individual nanotubes show evidence of band gap-selective protonation of the side walls of the tube. This protonation is readily reversed by treatment with base or ultraviolet light.read more
Citations
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Journal ArticleDOI
Optical properties of ultrashort semiconducting single-walled carbon nanotube capsules down to sub-10 nm.
TL;DR: In this article, single-walled carbon nanotubes (SWNTs) are typically long (≳100 nm) and have been well established as novel quasi-one-dimensional systems with interesting electrical, mechanical, and optical properties.
Journal ArticleDOI
Absorption spectroscopy of surfactant-dispersed carbon nanotube film: Modulation of electronic structures
TL;DR: In this paper, the effect of surfactant in dispersing single-walled carbon nanotubes (SWCNTs) to form conducting films was examined using UV-vis-NIR absorption spectroscopy.
Patent
Methods of making spatially aligned nanotubes and nanotube arrays
TL;DR: In this article, the authors present arrays of longitudinally aligned carbon nanotubes having specified positions, nanotube densities and orientations, and corresponding methods of making nanoteube arrays using guided growth and guided deposition methods.
Journal ArticleDOI
Optical characterization of DNA-wrapped carbon nanotube hybrids
Shin Grace Chou,H. B. Ribeiro,Eduardo B. Barros,Ana Paula Pires dos Santos,D. Nezich,Ge. G. Samsonidze,Cristiano Fantini,Marcos A. Pimenta,Ado Jorio,F. Plentz Filho,Mildred S. Dresselhaus,G. Dresselhaus,Riichiro Saito,Ming Zheng,G. B. Onoa,E.D. Semke,Anna K. Swan,M.S. Unlu,Bennett B. Goldberg +18 more
TL;DR: In this article, optical characterization of DNA-wrapped CoMoCAT carbon nanotube hybrids (DNAOCNT) and semiconductor-enriched DNAOCNT was carried out using resonant Raman spectroscopy (RRS) and photoluminescence (PL) experiments.
Journal ArticleDOI
Functionalized multiwalled carbon nanotubes as ultrasound contrast agents
Lucia Gemma Delogu,Gianpaolo Vidili,Enrica Venturelli,Cécilia Ménard-Moyon,Maria Antonietta Zoroddu,Giovannantonio Pilo,Paola Nicolussi,Ciriaco Ligios,Davide Bedognetti,Davide Bedognetti,Francesco Sgarrella,Roberto Manetti,Alberto Bianco +12 more
TL;DR: The use of functionalized multiwalled carbon nanotubes (MWCNTs) as hyperechogenic material is described, suggesting their potential application as ultrasound contrast agents, and their long-lasting ultrasound contrast properties are demonstrated.
References
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Journal ArticleDOI
CHARMM: A program for macromolecular energy, minimization, and dynamics calculations
Bernard R. Brooks,Robert E. Bruccoleri,Barry D. Olafson,David J. States,S. Swaminathan,Martin Karplus +5 more
TL;DR: The CHARMM (Chemistry at Harvard Macromolecular Mechanics) as discussed by the authors is a computer program that uses empirical energy functions to model macromolescular systems, and it can read or model build structures, energy minimize them by first- or second-derivative techniques, perform a normal mode or molecular dynamics simulation, and analyze the structural, equilibrium, and dynamic properties determined in these calculations.
Journal ArticleDOI
MOLSCRIPT: a program to produce both detailed and schematic plots of protein structures
TL;DR: The MOLSCRIPT program as discussed by the authors produces plots of protein structures using several different kinds of representations, including simple wire models, ball-and-stick models, CPK models and text labels.
Journal ArticleDOI
Crystalline Ropes of Metallic Carbon Nanotubes
Andreas Thess,R. S. Lee,Pavel Nikolaev,Hongjie Dai,Pierre Petit,J. Robert,Chunhui Xu,Young Hee Lee,Seong-Gon Kim,Andrew G. Rinzler,Daniel T. Colbert,Gustavo E. Scuseria,David Tománek,John E. Fischer,Richard E. Smalley +14 more
TL;DR: X-ray diffraction and electron microscopy showed that fullerene single-wall nanotubes (SWNTs) are nearly uniform in diameter and that they self-organize into “ropes,” which consist of 100 to 500 SWNTs in a two-dimensional triangular lattice with a lattice constant of 17 angstroms.
Book
Science of fullerenes and carbon nanotubes
TL;DR: In this paper, the authors present a detailed overview of the properties of Fullerenes and their properties in surface science applications, such as scanning tunnel microscopy, growth and fragmentation studies, and chemical synthesis.
Journal ArticleDOI
Constant pressure molecular dynamics simulation: The Langevin piston method
TL;DR: In this paper, a new method for performing molecular dynamics simulations under constant pressure is presented, which is based on the extended system formalism introduced by Andersen, the deterministic equations of motion for the piston degree of freedom are replaced by a Langevin equation; a suitable choice of collision frequency then eliminates the unphysical "ringing" of the volume associated with the piston mass.