By Peter Weiss
Scientists have long wanted to carry out chemical reactions one molecule at a time. In doing so, they imagined, they would probe the most intimate details of those transformations. Moreover, they’ve hoped they might find ways to create novel compounds that are impossible to make by conventional means. They also have anticipated assembling molecules that might be useful as nanometer-scale devices, they say.
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Now, for the first time, researchers have duplicated with individual molecules the full sequence of steps in a widely used chemical reaction. What’s more, they’ve made a photo album of the molecular makeover as it unfolds.