C60 molecules have an intriguing ball-shaped structure that suggests several interesting possibilities for motion on surfaces. Indeed, researchers have found that the passage of electrons through a bucky ball in a transistor is correlated to the spinning of the ball around its center of mass.
Moreover, since bucky balls look like molecular ball bearings, it has been thought that they may be useful as lubricants for use in automobile brakes. Now a team of researchers at the University of Bologna (Italy) and the University of Liverpool (UK) have carried out detailed molecular dynamics simulations to understand the motion of bucky balls on metal surfaces.
Francesco Zerbetto and Gilberto Teobaldi have found that C60 molecules exhibit a wide range of molecular motions on surfaces. The bucky balls spin and bounce on the surface and also show an intercage rattling motion that Zerbetto says is similar to that of billiard balls in a partly filled roll-a-rack triangle. The simulations have been carried out as a function of temperature and model the movement of several bucky ball molecules over times ranging up to one nanosecond. There is some transfer of charge from the gold surface to the bucky ball that helps in the adsorption of these molecules at the surface.
The researchers have found that with increasing temperature the cages move away from the gold surfaces resulting in a lower frequency of bouncing. The bouncing frequencies obtained by simulation match very nicely with experimental measurements of single-molecule bucky-ball transistors, corroborating the validity of the simulations.
The researchers have found that the bouncing of the cage on the surface and the intercage rattling govern the friction-related properties of the bucky balls on a surface. “The strong van der Waals interactions of the bucky balls with neighboring atoms makes the friction far too high for lubrication”, said Zerbetto, but he is hopeful that doping or chemical modification can be used to separate the bucky balls to get them to act more like ball bearings.
Author: Francesco Zerbetto, University of Bologna, http://www.ciam.unibo.it/sitcon/
Title: C60 on Gold: Adsorption, Motion, and Viscosity
Small 2007, 3, No. 10, 1694–1698, doi: 10.1002/smll.200700111
About Small: Micro and Nano: No small Matter. Science at the nano- and microscale is currently receiving enormous wordwide interest. Published by Wiley-VCH, Small provides the very best forum for experimental and theoretical studies of fundamental and applied interdisciplinary research at these dimensions. Read an attractive mix of peer-reviewed Communications, Reviews, Concepts, Highlights, Essays, and Full Papers.
Hunting pathogens at full force
22.03.2017 | Helmholtz-Zentrum für Infektionsforschung
A 155 carat diamond with 92 mm diameter
22.03.2017 | Universität Augsburg
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
22.03.2017 | Materials Sciences
22.03.2017 | Physics and Astronomy
22.03.2017 | Materials Sciences