Tag: molecule

Quantum computers reach deeper, find ground state of simple hydrides

Enlarge (credit: IBM ) Every time we discuss quantum computers, the headline tends to be that someone, somewhere is going to use the quantum to break your encryption and steal your student loan. If only that were true. But it is probably more realistic to think about quantum computers being used to solve quantum problems. And this has been demonstrated with recent chemistry calculations using a tiny quantum computer. If solving quantum problems with quantum computers sounds a bit circular, well, it is, but it is also practical. Think of it like this: every protein in your body has the structure it has because of quantum mechanics. And a physicist who is clever, but not intelligent, can write down an exact equation that describes that protein. But not even the most intelligent can solve that equation. Understanding molecules is hard A lazier physicist would write a computer script to solve the equation. But that won’t work either, because the time it takes to solve an exact description of the molecule will take longer than it takes to go from Big Bang to Heat Death. So we live with approximations. Approximations that are mostly pretty good but sometimes fail spectacularly. And, for some molecules, those approximations don’t speed up calculations very much at all. Read 13 remaining paragraphs | Comments

More:
Quantum computers reach deeper, find ground state of simple hydrides

Triangulene, reactive, magnetic relative of graphene finally produced

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

See the article here:
Triangulene, reactive, magnetic relative of graphene finally produced

Scientists capture images of molecules forming atomic bonds

For most of us, molecular bonding only really exists as a classroom concept. Some scientists at Lawrence Berkeley National Laboratory can now claim more tangible knowledge, however: they’re the first to have taken truly clear snapshots of bonding in progress. While trying to create graphene nanostructures and observe them with an atomic force microscope , a lab team spotted molecules forming their individual, atom-level links during a chemical reaction. The resulting shots were nearly textbook material, too — as the molecules were neatly placed on a flat surface, the researchers identified the order and nature of each bond. While the images will only be immediately useful for the nanostructure research at hand, they may add a welcome dash of reality to future chemistry lessons. Filed under: Science , Alt Comments Via: Phys.org Source: Lawrence Berkeley National Laboratory

Read the original:
Scientists capture images of molecules forming atomic bonds