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Two Lives

Scientists do any number of things, besides science

Roald Hoffmann

A Molecular Tetrahelix

2010-03MargHoffmannFB.jpgClick to Enlarge ImageAt dinner that evening, over a bottle of Corbières, Ansgar tells me part of his story. He always loved chemistry. And he always read; German literature was close to him. Originally from Cologne, Ansgar did his Ph.D. at the Free University of Berlin in the group of Hans Hartl. Now that was a name I knew well. Hartl and his students had made some copper compounds whose shapes had two, three or four tetrahedra that shared faces. I saw these once and thought, hey, why not an infinite chain of face-sharing tetrahedrals? David Nelson, a physicist at Harvard who once had been a student of mine, came up with the same structure in a different context, and Chong Zheng, a brilliant student fresh out of China, set to work figuring out for which elements might such a structure be stable.

2010-03MargHoffmannFC.jpgClick to Enlarge ImageWe thought we were original—until one of us saw a sculpture by Ted Bieler in front of the Marathon Realty Building in Toronto, with three such helices passing by each other. And then we saw Arata Isozaki’s 100-meter tower in Mito, Japan.

It looked like we weren’t that original. Actually, neither were the architects and sculptors (but they didn’t need to write footnotes, as we did), because this “tetrahelix” was the centerpiece of a chapter in Buckminster Fuller’s Synergetics!

In time, Hartl and his coworkers made the molecule, a copper iodide compound. It was as we had predicted; 12 orders of magnitude smaller than Isozaki’s tower, there it was.

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