The nanocar is a molecule designed in 2005 at Rice University by a group headed by Professor James Tour. Despite the name, the original nanocar does not contain a molecular motor, hence, it is not really a car. Rather, it was designed to answer the question of how fullerenes move about on metal surfaces; specifically, whether they roll or slide (they roll).
The molecule consists of an H-shaped 'chassis' with fullerene groups attached at the four corners to act as wheels.
When dispersed on a gold surface, the molecules attach themselves to the surface via their fullerene groups and are detected via scanning tunneling microscopy. One can deduce their orientation as the frame length is a little shorter than its width.
Upon heating the surface to 200 °C the molecules move forward and back as they roll on their fullerene "wheels". The nanocar is able to roll about because the fullerene wheel is fitted to the alkyne "axle" through a carbon-carbon single bond. The hydrogen on the neighboring carbon is no great obstacle to free rotation. When the temperature is high enough, the four carbon-carbon bonds rotate and the car rolls about. Occasionally the direction of movement changes as the molecule pivots. The rolling action was confirmed by Professor Kevin Kelly, also at Rice, by pulling the molecule with the tip of the STM.
The concept of a nanocar built out of molecular "tinkertoys" was first hypothesized by M.T. Michalewicz at the Fifth Foresight Conference on Molecular Nanotechnology (November 1997). Subsequently, an expanded version was published in Annals of Improbable Research. These papers were supposed to be a not-so-serious contribution to a fundamental debate on the limits of bottom-up Drexlerian nanotechnology and conceptual limits of how far mechanistic analogies advanced by Eric Drexler could be carried out. The important feature of this nanocar concept was the fact that all molecular component tinkertoys were known and synthesized molecules (alas, some very exotic and only recently discovered, e.g.
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Un moteur moléculaire est un objet de la taille d’une molécule ou d’un assemblage de molécules qui est capable de produire un travail mécanique ou un mouvement dirigé, ces buts ne pouvant être atteints que si de l’énergie est fournie au système. Les différences les plus importantes par rapport aux moteurs macroscopiques concernent la sensibilité des moteurs moléculaires à la viscosité de leur micro-environnement, et surtout à l’importance de l’agitation thermique.
The nanocar is a molecule designed in 2005 at Rice University by a group headed by Professor James Tour. Despite the name, the original nanocar does not contain a molecular motor, hence, it is not really a car. Rather, it was designed to answer the question of how fullerenes move about on metal surfaces; specifically, whether they roll or slide (they roll). The molecule consists of an H-shaped 'chassis' with fullerene groups attached at the four corners to act as wheels.
Les nanosciences et nanotechnologies (d’après le grec , « nain »), ou NST, peuvent être définies au minimum comme l’ensemble des études et des procédés de fabrication et de manipulation de structures (physiques, chimiques ou biologiques), de dispositifs et de systèmes matériels à l’échelle du nanomètre (nm), qui est l'unité la plus proche de la distance entre deux atomes. Les NST présentent plusieurs acceptions liées à la nature transversale de cette jeune discipline.