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Rethinking Molecular Machines

One of the great joys of being a chemist is making stuff. Like architects working on the smallest of scales, chemists can create the most ingenious molecules, limited by only their imaginations and the rules of chemical bonding. Perhaps nowhere is this creativity of synthetic chemistry more evident than in the field of artificial molecular devices—where single-molecule ratchets spin, motors whir, and machines maneuver all by virtue of chemical reactions and interactions. But after two decades of molecular whirligigs and doodads, Northwestern University’s J. Fraser Stoddart, one of the field’s leading researchers, and his Northwestern colleague, Bartosz A. Grzybowski, an expert in nonequilibrium chemical systems, are taking a hard look and asking, “Can artificial molecular machines deliver on their promise?” That provocative question is the subtitle of an article the two published, along with Ali Coskun of the Korea Advanced Institute of Science & Technology; R. Dean Astumian of the ...