[HN Gopher] Perfluorocubane is (as you would expect) weird ___________________________________________________________________ Perfluorocubane is (as you would expect) weird Author : kens Score : 182 points Date : 2022-08-23 15:52 UTC (7 hours ago) (HTM) web link (www.science.org) (TXT) w3m dump (www.science.org) | kurupt213 wrote: | Maybe we should stop perfluorinating every organic molecule | perihelions wrote: | Octa _nitro_ cubane also exists (first synthesized in 1999), and | is the high explosive with the highest known detonation velocity. | I think the bond strain in the cubane structure is a large factor | in that. | | https://en.wikipedia.org/wiki/Octanitrocubane | KSteffensen wrote: | I think having as many nitro groups as carbons in there might | also be a factor | notimpotent wrote: | I love how excited the author is about this post. It sounds like | some promising discoveries are in the works. | | Of course I have no idea what any of this means. Maybe somebody | could share a layman's explanation? What would be the benefit of | "hold a free electron in the middle of that cube"? | btilly wrote: | The excitement is that someone did a lot of work and verified | we got the science right on a bizarre compound. | | How to explain it? Let's go to the foundations. Let's start | with the periodic table: | https://en.wikipedia.org/wiki/Periodic_table. | | Matter is made up of atoms. Each atom has a nucleus and a cloud | of electrons around it. Inside the nucleus we have some number | of protons and neutrons. The number of protons determines which | element it is. The number of protons + neutrons is basically | how heavy it is - that's called an isotope. Isotopes don't | matter for chemistry, so we'll ignore that. | | For example if you have 6 protons then you're the 6th element. | Namely carbon. And 9 electrons gives the 9th element, fluorine. | Also protons carry a positive charge, so you'd generally have | the same number of electrons as protons. But not always. If an | atom or molecule has a different number of electrons and | proteins then it is called an ion. More on that soon. | | Next up, we have quantum mechanics. In a classical world, the | electrons would want to go to the nucleus to hang out with the | protons. In a quantum mechanical world, uncertainty in position | times uncertainty in momentum has a minimum. Since electrons | are light, if we know that an electron is in the nucleus, it | probably has a momentum so big that it will soon NOT be in the | nucleus. Therefore the best that the electron can do is be | somewhere in a kind of probability cloud around the nucleus. | Those clouds are called orbitals. | | The exact shapes of those clouds have been worked out, and are | called orbitals. Orbitals form into shells. Each orbital can | contain 0, 1 or 2 electrons. Each shell has a finite (usually | fairly short) list of orbitals in it, and all of this has been | worked out. This is why the periodic table (see | https://en.wikipedia.org/wiki/Periodic_table again) is arranged | into columns. Each column usually has the same stuff in its | outer shell, and therefore is likely to do somewhat similar | things chemically. | | Most of chemistry comes from one rule. Atoms like having their | outer shell either totally empty, or totally full. They have 2 | ways to do. The first is the _ionic bond_. That 's where one | atom gives another an electron, making both into ions. The ions | then hang out together and are called a salt. The second is a | _covalent bond_ , where 2 atoms share an electron each to give | each an extra part time electron, making both happy. In the | periodic table the farther towards the right and top you are, | the more you want a full outer shell. And the farther towards | the left and bottom you are, the more you are willing to give | up electrons if someone asks. | | In fact the elements on the left side care so little for their | outer electrons that, when they get together, they let their | outer electrons wander around freely. Those electrons make | things shiny, and conduct a current when they all move | together. Those are metals. By contrast the ones on the right | are non-metals - they can steal from metals or share with each | other. How many depends on which column they are in. | | The very last column is the noble gases. They have a full outer | shell and would like it to remain that way, thank you very | much. So they don't get involved in this chemistry nonsense. | | Now let's talk about the stuff involved in this article. | | Fluorine, element 9, is the farthest to the top and right you | can get without being a noble gas. It wants one electron and is | vicious about getting it. Trying to get it do something unusual | usually requires making it temporarily very unhappy. An | unhappiness that it is perfectly willing to resolve by reacting | with the chemist. This is not an idle threat - histories of | fluorine usually start with a list of famous chemists who were | killed or maimed in this way. However once it has reacted, it | is often very stable. We stick fluoride into toothpaste and | cook with teflon - both of which contain fluorine. | | Carbon, element 6, comes 3 columns before. Its outer shell has | 3 fewer electrons, so it wants 3 more. Making 4 bonds. But | where fluorine is vicious, carbon is polite. This makes carbon | the tinker toy of complex chemistry. Which is how it became the | backbone of pretty much everything required for life as we know | it. | | Now what does this compound look like? | | Let's start with a box. At each corner you put a carbon. Each | corner is connected by edges to 3 other corners. That leaves | each carbon short one bond. So we stick one fluorine off of | each corner. That gives us the diagram at the top right of the | article. | | Now remember that fluorine is vicious, while carbon is polite. | Yes, each fluorine is sharing an electron with a carbon, but it | is rather unequal. The electron hangs out with the fluorine a | lot more than with the carbon. Therefore the fluorines wind up | negatively charged (the extra electron spends more time with | them). The carbon atoms therefore wind up with a corresponding | positive charge. And all of these positive charges, in theory, | make the very center of the box a perfect place for a passing | electron to take up residence. An electron that is not part of | any atom, just sitting there enjoying a nice home. That extra | free electron where an electron normally wouldn't be makes the | whole thing an ion. | | So it is cool that the theory works out. But in order to do it, | some chemist had to do stuff with fluorine that nobody sane | wants to happen anywhere near them, let alone be actually doing | doing in a lab. | qorrect wrote: | I like your word choices can you teach me chemistry ? /s | | No but really if you have any book suggestions for an | engineer wanting to learn more chemistry I would appreciate | it! | bonzini wrote: | So the anion is simply C8F8+ ? That is weird indeed. | nanofortnight wrote: | C8F8- | | The extra electron makes it negatively charged by -1 (thus | an anion). | sulam wrote: | His excitement is due to the unlikeliness of the result, more | than its usefulness. All of the compounds discussed are | amazingly reactive, and working with them, even in a lab, is | incredibly difficult. | cosmojg wrote: | The way this guy writes about organic chemistry has me swooning. | beanders wrote: | What are the potential applications? I read the article, it was | pretty interesting but I only saw things that would be odd to an | expert (which I am not). Sure it's a cool shape, but what does it | do? | samus wrote: | It seems that it was evidence for theoretical approaches to | predict molecule bond behavior. The author mentions DFT, which | I assume stands for Density Functional Theory. | chrisbrandow wrote: | Yes | doug_life wrote: | Derek Lowe's "Things I Won't Work With" entire series is both | educational and highly amusing. This is another good article: | https://www.science.org/content/blog-post/sand-won-t-save-yo... | narrator wrote: | Hydrofluoric acid, mentioned in the article, is terribly toxic | stuff. I can see why he doesn't want to work with it. A drop of | the concentrated liquid on the skin can kill. Unfortunately, I | think it's critical to the semiconductor industry and there's | nothing that could conceivably replace it. | tolstoshev wrote: | This one is my favorite: https://www.science.org/content/blog- | post/things-i-won-t-wor... | greenbit wrote: | "At seven hundred freaking degrees, fluorine starts to | dissociate into monoatomic radicals, thereby losing its | gentle and forgiving nature." | | Lol - that's the best | ryandvm wrote: | Yeah, reading this article I was amused with the author's | writing style and reminded of the "Things I Won't Work With" | blog. Lo and behold, it's the same guy. | EricE wrote: | Along the same lines he reminds me of one of my favorite | youtubers: https://www.youtube.com/c/styropyro | [deleted] | UncleSlacky wrote: | Similarly, "Ignition!" is a classic of the genre: | | http://www.sciencemadness.org/library/books/ignition.pdf | selimthegrim wrote: | Maybe I'm slow here, but the authors said they couldn't get a | molecular ion in mass spec, but the ESR shows an electron in the | center like would be expected for an anion? Is that a radical? | Did they mean they couldn't get a cation? | bilsbie wrote: | Would this be useful for quantum computing somehow? | | Or maybe some kind of sensor? | | Also could a cell be programmed to make this or do cells not have | the ability to manipulate flourine? | metalliqaz wrote: | If I'm reading the article right, the material is not stable | (and also very very difficult to make). So I'm guessing this is | probably just an interesting project to check how well current | atomic bonding models fit reality. | cscheid wrote: | Lowe is being funny and calling back to his classic "Things I | won't work with" series (which is also linked to in a | different comment). | | One of the things you learn just from that series is that | anything with this much fluorine jammed into it is just | asking for trouble. Case in point, | https://www.science.org/content/blog-post/things-i-won-t- | wor... | paulmd wrote: | Azidoazole Azide is another classic from the "take a nasty | little functional group and build a whole molecule out of | them" family. | | https://www.science.org/content/blog-post/things-i-won-t- | wor... | | Fulminates and Azides are known for their physical | sensitivity, they're the primary explosive used for the | primers in gun cartridges. Azides are generally more | sensitive than fulminates - mercury fulminate is an older | primer compound where mercury azides are quite unstable and | reactive. | | Azidoazole Azide is basically an azide group bonded to an | azole ring... azole is like pentane except with a nitrogen | ring. So basically just one giant pile of nitrogen bonds | looking for a reason to un-bond. | | See also, Hexanitrohexaazaisowurtzitane, although the name | isn't nearly as suggestive, but that's a nice little | molecular diagram right there too lol. "Thrillingly | nitrogenated", would probably be the description. | | https://www.science.org/content/blog-post/things-i-won-t- | wor... | UncleSlacky wrote: | See also "Ignition!": | http://www.sciencemadness.org/library/books/ignition.pdf | daniel-cussen wrote: | Am reading it upon your recommendation! | astrange wrote: | I still want to know what isocyanide smells like. The "it | smells bad" articles just say things smell bad but not | exactly how. | | https://www.science.org/content/blog-post/things-i-won-t- | wor... | | https://www.science.org/content/blog-post/things-i-won-t- | wor... | | https://www.science.org/content/blog-post/things-i-won-t- | wor... | mkarliner wrote: | It's always such a joy reading these posts. I'm not a chemist, | although my father would have loved me to be, but the sheer style | and erudition, makes them compulsive reading | Alan_Dillman wrote: | "Forget everything you know about slipcovers." | | I also had no expectations about something called | Perfluorocubane. | gtmitchell wrote: | Wow, someone pulled off that synthesis? I'm impressed! | | For those who are wondering if this has any practical | applications, the answer is almost certainly no. At best, someone | might look at the synthetic pathways used to produce | perfluorocubane to attempt to make something similar. It has | really unusual spectroscopic and physical properties, which is | pretty cool, but mostly in the sense of being a curiosity rather | than being something you can do something with. | | Imagine this as being the chemistry version of someone managing | to get Doom to run on an electric toothbrush or something. It's | interesting and amusing to know it's possible, but you're never | actually going to start using your Sonicare for gaming. | dudeinjapan wrote: | It's a Time Cube. In a single rotation of the octafluorocubane, | each Time corner point rotates through the other 3-corner Time | points, thus creating 16 corners, 96 hours and 4-simultaneous | 24-hour Days within a single rotation. | vitiral wrote: | So it looks like a British phone booth and transports a | Doctor around the Galaxy? | jrumbut wrote: | I always get Time Lords and Time Cubes confused. | nextaccountic wrote: | Could this thing be attached to a solid substrate, perhaps a | semiconductor, and remain in place? Like in a computer chip | | What about using that free electron in the middle to do | computing? Perhaps a quantum computer or something | | I mean that's what reminded me: quantum computers often trap a | charged particle, perhaps an ion or electrons, and use it to | store qubits. This stuff here seems to be a perfect electron | trap. Or isn't it? | | (note, I'm just throwing ideas in the air, I know almost | nothing of chemistry, semiconductors or quantum computers) | YakBizzarro wrote: | Not far from reality, indeed. Every time you have some | molecule with a free electron, you can perform Electron Spin | Resonance on it. You take a small amount of the molecule, put | in a strong magnectic field, and with microwave you could | drive the transition between the down and up state (parallel | and antiparallel to the magnetic field). However, with a | conventional spectrometer you can't control a single spin, | because its signal would be tremendosly low, you would need | at least ~10^13 molecules (maybe even less nowadays). If you | want to use a single molecule, you need to connect to some | kind of nanofabricated structure, in order to control and | read it out. It's feasible, many works showed that, but very | very difficult to engineer. You could spend most of your phd | trying that (a pretty common tale in the field). | throwawaymaths wrote: | That's actually not a terrible idea! But sadly the ion seems | to be unstable, which means ithe electron is not 'trapped' | and rather free to interact with it's cage. | Pulcinella wrote: | Regular cubane and related compounds have been investigated as | race fuels. The bond angles means that extra energy is stored | (basically via tension in the bonds due to those extreme | angles) compared to 4 ethane molecules (which add up to the | same number of carbon atoms, hydrogen atoms, and bonds as one | cubane molecule). So your race car could weigh less while still | having just as much fuel energy. I think most race series have | standardized fuel across competitors now so it's unlikely | anyone will continue with the research. | mcguire wrote: | Dang it! And I was just getting together venture capital for | industrial scale production. | atwood22 wrote: | Wouldn't having an ion like this be useful? I'm not an expert | in Chemistry, but most ions will either return or gain an | electron at the first opportunity. This compound, on the other | hand, likes having an extra electron. | daniel-cussen wrote: | Yeah it opens up possibilities. Not worth patenting it or a | near-neighbor. | | But this will lead places. | | In addition reduce search spaces. That's what it's all about | with molecules these days. Search spaces. | londons_explore wrote: | This comments section doesn't look so different to one under a | youtube video about how to make 'free energy' from water. | | When a lot of people pile in with their opinion on a topic they | don't understand... | blackoil wrote: | At least, the tone suggests people are aware of the fact that | they know nothing about the topic. On Youtube everybody is an | expert on 'Free Energy'. | jquery wrote: | Can someone explain exactly how weird it is? It sounds like a | monster was created but I don't really understand its properties | beyond it being very acidic (?) | devilbunny wrote: | You have a sterically strained carbon structure (it does NOT | want to make a cube). Then you saturate it with the one of the | most aggressive atoms in existence, all without blowing up the | carbon structure or your lab. | | That molecule would _really_ like to blow up. | PlasmonOwl wrote: | Just to weigh in as a chemist. A high level of skill and patience | went into the creation of this. Fluorine is one of the nastiest | things youll find in a lab. HF is no joke. | sudosysgen wrote: | There is a video series on YouTube of an organic chemistry PhD | student attempting to synthesise cubane in his garage from | readily accessible materials. It may put this feat into a bit of | perspective as a non-chemist. | | https://youtube.com/playlist?list=PLnafk93vhO36cccP0p83hcop3... | bediger4000 wrote: | I like how the author assumed that readers have all kinds of | abstruse chemical knowledge: lots of "as you would expect" | phrases after chemical jargon. | ufo wrote: | This is an area where comment threads can shine. For most | questions, if you ask it early enough then odds are that you'll | get a good explanation from someone. | anon_123g987 wrote: | Every field does this trolling in some form. The sentence "The | proof is trivial and left as an exercise to the reader." should | be familiar for everyone who studied Math. | mattkrause wrote: | In that vein, this spoof captures the experience of reading a | Springer "Introductory" textbook: | https://kieranhealy.org/blog/archives/2022/05/20/every- | sprin... | gweinberg wrote: | Hey, I'm reading a Springer book now, and it's not so bad. | It's humbly titled "All of Statistics", and I think I | understand at least 2/3 of it. So far. | anon_123g987 wrote: | Nah, it's standard engineering procedure: | https://i.imgur.com/rKPe0Av.jpeg | jordan_curve wrote: | I never took anything past high school chemistry and I managed | to understand it. It's not really that abstruse. My background | is a bunch of wikipedia articles and chemistry youtube videos. | devilbunny wrote: | It's not a general-purpose blog. | | My B.S. in chemistry is 25 years old, and I still got the story | despite not working in the field [edit:sp]since. It should make | sense if you've had organic and qualitative analytical | chemistry, which are sophomore- and junior-level undergrad | classes. _Given his audience_ , that's pretty reasonable. | dekhn wrote: | I will never forget the diels alder reaction. 30 years since | I took o-chem | dvh wrote: | I have a conjecture that if you visit some exotic materials' | Wikipedia page and in top right corner is not something you can | touch, it's probably a scam. | yuan43 wrote: | Synopsis: | | 1. Quantum mechanics predicts that the target molecule can | accommodate an electron inside (electron-in-a-cube). | | 2. A sample of the target molecule was prepared, and yes, it | involved elemental fluorine, a very difficult substance to handle | safely and one notorious for nonproductively chewing up just | about everything you give it. | | 3. Analytical results were consistent with the structure. | | 4. The substance's electrochemistry at low temperatures was | consistent with the uptake of an electron at the predicted | potential. Fine structure of results are consistent with the | electron-in-a-cube idea. At room temperature, the results | indicate decomposition. | | 5. Bonus: the electrochemical results suggest the electron-in-a- | cube assembly is rotating unexpectedly. | | This is a really good example of basic science in action. | Observation (some molecules envelop other molecules), | generalization (maybe a molecule could envelop an electron), | hypothesis (calculations suggest _this_ envelope in particular | would work, and would yield these specific observations), | experiment (figure out how to make the thing, make it, then | measure the predicted properties), update hypothesis (in this | case, the electron-in-a-cube is rotating unexpectedly). | | It's also a good example of why it's a good idea to do | experiments you think will "work". Sometimes they don't work and | your hypothesis does in fact suck. Sometimes they work exactly as | you expect and you can add that to the pile of evidence you | already have in support of the hypothesis. And sometimes you get | a surprise. | [deleted] | perihelions wrote: | Just checking, this experiment *confirms* that there's a lone | electron inside the cubane cage? | | - _" At very low temperatures (77K, matrix isolation) in an ESR | apparatus, though, you can indeed see the spectrum of the | predicted "electron in a cube", split just the way that you would | have drawn it out."_ | | (It's written for an audience who doesn't need to be reminded | that "ESR" means Electron Spin Resonance, and that is not me!) | ajkjk wrote: | > You will note the explanatory style that is characteristic of | my long-delayed book, "Quantum Mechanics: A Hand-Waving | Approach". | | I would read the crap out of this. ___________________________________________________________________ (page generated 2022-08-23 23:00 UTC)