If each bit of digital data could be represented by a single molecule, memory devices could shrink by more than three orders of magnitude. But manufacturing such devices requires a simple way to keep molecules straight and organized. A team led by University of California, Riverside, chemist Ludwig Bartels has come up with a possible solution: molecules that walk in a straight line, without guides or templates.

Called 9,10-dithioanthracene, or DTA, the new molecule sports two sulfur atoms protruding from a central structure made of linked benzene molecules. The Riverside researchers deposited DTA molecules on a smooth copper surface and cooled them to about -223 degreesC; they found that the molecules would then form rows and begin to move in straight lines -- almost as if they were walking.