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.
A novel socio-ecological approach helps identifying suitable wolf habitats
17.02.2017 | Universität Zürich
New, ultra-flexible probes form reliable, scar-free integration with the brain
16.02.2017 | University of Texas at Austin
In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".
Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
20.02.2017 | Materials Sciences
20.02.2017 | Health and Medicine
20.02.2017 | Health and Medicine