Nanoparticle (image) American Chemical Society Caption In a step forward for nanotechnology, scientists are reporting an advance that allows the controlled movement of individual molecules without help from outside forces. Shown is a model of the atomic structure of a silicon nanocrystal. Credit National Science Foundation Usage Restrictions None Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.