Triangulene. No matter how hard you try, you can’t put double bonds on the middle rings without having a carbon atom form five bonds, which it refuses to do. So you end up with unpaired electrons instead. A lot of organic chemistry feels like an episode of Mythbusters , if a bit of an undramatic one. Imagine a couple of chemists sitting at a white board, asking each other, “Is it actually possible to build this thing?” Getting a PhD can often depend on figuring out how to overcome the challenges of constructing a molecule. Sometimes, the challenges come because the starting materials won’t react with anything. Sometimes, the challenge is that the products will react with everything , often with explosive consequences. But clearing these hurdles is usually more than an intellectual curiosity; in many cases these odd molecules can tell us about basic principles of chemistry. The molecules may also have useful properties that we’d like to study in the hope that we can figure out how to make a stable molecule that behaves the same way. In the latest triumph, a Swiss-UK team has managed to make a molecule called triangulene. It’s a strange beast: a flat triangle of carbon that has an odd combination of bonds that leave a couple of electrons free. These electrons are expected to give it magnetic properties, but we haven’t been able to confirm this because the molecule also reacts with everything it comes in contact with. The trick to making it was crafting individual molecules by hand—a hand that operated a scanning-tunneling microscope. Read 8 remaining paragraphs | Comments

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Triangulene, reactive, magnetic relative of graphene finally produced