Boron Buckyballs: B80 cages in the lab | Hacker News Reader

Boron Buckyballs: B80 cages in the lab

cen.acs.org

124 pointscrescit_eundo36 comments

While exciting, please note that they only were able to record a photoelectron spectrum and back this up with a lot of theoretical work, which is far from a conclusive proof of identity. Right now we know they made some yet-unknowm boron compound with a very weird, symmetrical, photoelectron spectrum... but imo the information density in these spectra isnt super high.

Without a mass spectrum (telling you at the very least that they made a pure compound of 80 boron atoms) or even better a bulk synthesis route (extremely difficult, but giving you an amount of compound you can actually look at & investigate further) this should be filed under "tantalizing discovery but no definitive proof of existence".

I'd love to be proven wrong tho in my scepticism because this is one exciting molecule.

Boron always seemed like an under-studied element to me. Starting from the bottom, hydrogen of course is very well understood, helium not useful for much, lithium used for many things, and beryllium interesting but unfortunately toxic. Next is boron. Low toxicity, light weight, interesting electron configuration. Compounds like boron nitride and boron carbide have remarkable properties, but seem to get less attention than carbon. Not sure why.

Some have noticed. My top example. "solidstate protein synthesis". Interest should asymptotically approach that in orgo since boron makes any cooking more fun,just like butter (garam bleng for the vegans, sorry)

https://www.sigmaaldrich.com/SG/en/technical-documents/techn...

Remarkably pleasant to work with, unlike the class of compounds which include

https://en.wikipedia.org/wiki/Zip_fuel

And

Merlin's TEA-TEB

Easter egg:

At least one town https://en.wikipedia.org/wiki/Boron,_California

(Carbon has too many)

> helium not useful for much

Maybe not for a chemist, but as a physicist it’s certainly useful. Liquid He cooling, Bose-Einstein condensation, superfluidity, p-wave triplet pairing in He-3, etc. while being basically chemically inert!

For many properties, boron has an intermediate behavior between carbon and silicon. For a few properties, boron resembles more phosphorus than silicon or carbon (mainly because of a closer ionic size, which makes borates somewhat intermediate between phosphates and silicates).

But both carbon and silicon are extremely cheap and abundant, many orders of magnitude more abundant than boron. Even phosphorus is several orders of magnitude more abundant than boron.

So in many cases there are carbon and/or silicon compounds (or sometimes phosphorus compounds) with properties not very different from some boron compounds. For instance in some applications where boron nitride or boron carbide would be desirable one of diamond, graphite, silicon nitride or silicon carbide may also be acceptable.

Therefore the boron compounds are typically used only when their specific benefits are so great that they overcome any cost difference over possible carbon-based or silicon-based or phosphorus-based substitutes.

In living beings (e.g. in plants), the role of boron is similar to that of phosphorus, both are used in their oxidized form, i.e. as phosphates or borates, which both have an affinity for binding to carbohydrates (like phosphate in nucleic acids) or sometimes to other alcohols (like in cellular membranes).

Complete title is: "Introducing boron buckyballs: Theory predicts B80 cages can’t be made. Experimentalists just proved otherwise"

That, also, would be incorrect. The original major theory paper did the opposite: Nevill Gonzalez Szwacki, Arta Sadrzadeh, and Boris Yakobson predicted a stable B₈₀ fullerene cage in 2007, calling it an unusually stable boron cage and saying it was likely to self-assemble under proper conditions. What later theory challenged was not whether a B₈₀ cage could exist at all, but whether the soccer-ball B₈₀ buckyball was the lowest-energy structure. Then, of course, accuracy was sacrificed in the name of clicks.

Yes but it contradicts the article

Curious to see when a post from OpenAI will appear with the corrected theory or something. This seems to be an ideal scenario for them to go after another scientific case. They have the theory, they have the experimental proof that it’s wrong, exactly what you need for an agentic loop to do its work.

Or maybe what works in math doesn’t work with chemistry?

>[theorists disagree] that the discrepancy is as significant as it appears.

It was predicted by decade old "theory" (with a single equation,and it seems that the original paper has no equations at all)

so OAI/DeepMind can quietly check if it's in the training or if they can extrapolate, yes

https://arxiv.org/abs/0803.2752

https://cen.acs.org/articles/85/i18/Boron-buckyball-predicte...

but is it worth the effort from a PR perspective for them? I guess we will have to wait and see.

What a bunch of borons!

this boronic thing (negative ion, really) they _might have seen_ has 241 (valence) electrons..

You'd expect a nice 240 given the symmetry, not a prime number

Or maybe a less baity reason is those hints of B_80^- have captured H+ "nuclei", turning into almolecular atoms!

Not oxyboronic at all

What do you mean by "turning into almolecular atoms"?

Typo. No "al-" prefix

It is a lot less uniform than carbon c60. I wonder what weird properties that will give it.

It's quite "uniform" (symmetrical). It's essentially the same structure as the 60-atom ball, but with an additional atom at the centre of each hexagon.

Having only just learned what DFT is by reading this article, could someone familiar with the field opine on how significant it would be to discover a physical system that conflicts so much with its predictions?

DFT is an approximation. It's good for some molecules and it's bad for others. There are many methods under the DFT umbrella, so it's more complicated. Some method are good for some molecules, other methods are good for others. Some molecules are easy and can be approximated by many methods, some molecules are hard and no method is good for them.

It's not my area, but I'm sure B80 is one of the tricky ones. In general anything with Boron is hard. This in particular probably have some electrons that are not inside a "bond" between two atoms, but are distributed in the whole molecule. Something like benzene, that has a few electrons in a circular ring of 6 atoms, but in this case it's 3D and with 80 atoms. You need some special cases for the ring in benzene and similar molecules.

The main problem is that solving the molecules exactly needs exponential time in a classical computer. If H is the number of Hydrogen and X is the number of very light atoms, it's like (expt(2*(H+5X)))^3. Heavy atoms enter with a bigger multiplier. And that bound already has a lot approximations and simplifications. So for not trivial molecules and for big molecules that are important in biology with X~=100 or 1000 you must do some approximations.

DFT is one of them. Most of the time it works, specially if you choose the correct method inside the DFT label. I'm not surprised that there are exceptions. If confirmed, probably someone will create a new tweak inside of one of the method to fix the discrepancy.

This is conventional DFT which is O(N^3)

Original paper, not a single equation:

https://web.archive.org/web/20240129185108/https://www.owlne...

The N^3 is further reduced by high symmetry. Because structure relaxations are usually convergent, the 2007 DFT and MD calculations can be run on a regular laptop today, maybe even without a GPU!

The discrepancy has been exaggerated by the experimentalist, TFA quotes the original theorist. This is not the first time, and probably not the last time, that c&en has oversold an experimental result.

Thanks for taking the time to explain!

I wonder what the largest molecular “ball” that we could build would be? How cool to have one you could see or hold?

I guess it would be similar to the sensation of playing with a sheet of graphene.

about DFT not predicting it: could it be that they used a non-relativistic model?

Given the energy scales involved, it's more likely that the issue lies with the approximations DFT makes to quantum mechanics, rather than the approximations quantum mechanics makes to quantum field theory.

I agree. There are some important relativistic correction for heavy atoms like Gold where the inner electrons are "rotating" too fast near the nuclei, but for Boron it's not necessary to do that correction.

but, don't you need it already for C60?

As far as I know, no relativistic corrections in C60. They are "slow moving" electrons, you can get away with non-relativistic QM. So I guess it's not necessary to make relativistic corrections in B80.

It's very different in a heavy atom like Gold. The charge of the nuclei is x10 of the charge of the Carbon nuclei, so the inner electrons are x10 closer and the "speed" is x10 faster. [1] I don't remember the numbers, but some google search claims 2.7%c for Carbon and 58%c for Gold. You definitively can ignore the relativistic corrections at 2.7%c, there is a square somewhere in the formula and the corrections is like ~(1-(2.7/100)^2).

As the G...GP says, the problem are the weird parts of Quantum Mechanics that are ignored to get a fast method to get an approximation in DFT.

[1] There are some technical details to define "speed", but just squint your eyes and ignore the cries of physicist.

This is surely extremely exciting for theorists then!

Not all.

It is only exciting for these theorists who predicted it. They can now hardly wait for a proper synthesis?

https://cen.acs.org/articles/85/i18/Boron-buckyball-predicte...

It's certainly exciting for theorists who predicted its impossibility, and exciting for any other theorists interested, whether they trusted or doubted the theoretical results.

I wonder what you can do with B80?

I'm waiting for it to show up in Derek Lowe's delightful blog, "Things I will not work with."

I don't see why it would. Did C60? Are fullerenes known for unusual reactivity? I'd expect the opposite, if anything.

No, but boron compounds are notoriously reactive and unstable. My dad, brother, and spouse, all worked on boron chemistry during their careers. So I learned a little bit about it, though I'm not a chemist myself. You treat every new boron compound as if it's about to detonate.

Hehe... Any new chemical compound will not be considered hazardous / toxic etc, until a significant amount has been released into the environment. So

1. Figure out how to mass-produce the stuff 2. Come up with some totally unnecessary household & industrial applications, that involve the chemical's release into the environment 3. Find out it's hazardous. Or toxic. Or both. And -bonus points!- doesn't break down.

In that order.

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