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Long Live the Intermediate!

What’s in between in a reaction matters just as much as what sets it off

Roald Hoffmann

Equal Time

To return to the metaphor of creating social change, I would suggest that real change is not the product of a single catalytic substance, like the personality of a leader, or a formula that imposes or removes a tax. Change—be it of American attitudes toward conserving electricity, or abandoning racial or gender stereotypes—will come about through many small actions by individuals. In a way, these are the intermediates.

Perhaps I have sought a little too hard to privilege the intermediate. A fairer statement of the realities of chemistry might be the following: Finding a catalyst gets you chemical action (and potential profit); finding a reaction intermediate gets you the mechanism. I guess that as a theorist, I’m a man of understanding, not an action hero. Or maybe, just maybe, in rooting for equal time for reaction intermediates, I’m just for the molecules less hailed, the ones less capable of evoking the mythological structures that reside in our minds.


I am grateful to Barry Carpenter, Geoff Coates, Brian Crane, Prasad Dasari, Bruce Ganem and Paul Houston for comments and suggestions.


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