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Science

New Results Contradict Long-Held Chemistry Dogma 316

An anonymous reader writes "Researchers have found that the long-held belief that only the outer, valence, electrons of an atom interact may be false. Computer simulations have shown that at pressures like those in the center of the Earth the inner, core, electrons of lithium also interact."
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New Results Contradict Long-Held Chemistry Dogma

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  • by Angst Badger ( 8636 ) on Saturday August 02, 2008 @12:58PM (#24448663)

    Dogma?

    If it was dogma the priests of chemistry would be denying the evidence and punishing its discoverers.

    That's the difference between science and religion. For science, new information enlarges our understanding of the world. For religion, new information only threatens sanctified prejudices.

    • by LaskoVortex ( 1153471 ) on Saturday August 02, 2008 @01:13PM (#24448799)

      If it was dogma the priests of chemistry would be denying the evidence and punishing its discoverers.

      Evidence you are not a scientist. The word "dogma" just has a different meaning from what you are used to when talking about science. To wit: "The Central Dogma" [wikipedia.org]. You should call up Francis Crick and tell him he was using that word wrong. Maybe they will posthumously take back his Nobel Prize.

      • by rangek ( 16645 ) on Saturday August 02, 2008 @01:21PM (#24448871)

        You should call up Francis Crick and tell him he was using that word wrong. Maybe they will posthumously take back his Nobel Prize.

        No need. Crick has already acknowledged that he really didn't understand the meaning of the word "dogma" when he used it. However, his ideas were so grond breaking that the word itself has changed/added meaning to accommodate him.

        • by Graff ( 532189 )

          However, his ideas were so grond breaking that the word itself has changed/added meaning to accommodate him.

          I just want to know: what did the poor gronds ever do to Francis Crick that they deserved to be broken?

          ;)

      • I am a scientist. Francis Crick was using the wrong word (he would not disagree with that statement). "Dogma" does not belong in science. When eminent scientists name something in a stupid way, we tend to revise the wording a generation or two later. That's why we have top and bottom quarks instead of truth and beauty. They didn't have to take any Nobel prizes away to do that. We use "momentum" instead of "quantity of motion," but no one suggests Newton was a bad scientist because of it. In chemistry

      • by fermion ( 181285 )
        Biology, certainly not chemistry of physics. Dogma is mostly used today by those who wish push science back into the realm of superstition so they can mutilate and burn. Those enlightened by the scientific method use different terminology [wikipedia.org].
      • To wit: "The Central Dogma". You should call up Francis Crick and tell him he was using that word wrong.

        Okey doke. I'll go get my Ouiji board...

    • So just to get this straight: science always lives up to the ideals of the best of scientists, while religions all conform to the practices of the worst practitioners?
      • Pretty much.

        • Re: (Score:2, Interesting)

          by g0dsp33d ( 849253 )
          This is slashdot. It leans far left and toward science and aways away from Microsoft, MPAA/RIAA, and SCO.

          For supposedly trying to be neutral, a lot more posts negative of religion or the right get modded up. The GP could be -1 troll as easily as +5 insightful. Unfortunately the modding doesn't work and you have to post AC if your not following the official prejudices.
          • by MillionthMonkey ( 240664 ) on Saturday August 02, 2008 @01:57PM (#24449197)

            For supposedly trying to be neutral, a lot more posts negative of religion or the right get modded up.

            Who promised you "neutrality"? Good posts that are negative of religion or the right are just easier to write. You see more of them modded up because more of them are posted.

            Instead of whining that everyone is biased, why don't you just mod up posts you agree with if you don't like it, or start writing posts "positive of religion or the right" that are actually insightful or interesting?

            • Neutrality was probably the wrong word.

              Do not promote personal agendas. Do not let your opinions factor in. Try to be impartial about this. Simply disagreeing with a comment is not a valid reason to mark it down. Likewise, agreeing with a comment is not a valid reason to mark it up. The goal here is to share ideas. To sift through the haystack and find needles. And to keep the children who like to spam Slashdot in check.

              I think if this was taken more seriously, people wouldn't have to post as AC when posti

          • Reality has a liberal bias.

          • This is slashdot. It leans far left and toward science

            For the uniformed there is a banner at the top that says "SLASHDOT News for Nerds. Stuff That Matters." I know, it's "shocking" that it would lean toward science.

      • by rbanffy ( 584143 )

        No, but science has far better mechanisms to defend itself than religion.

        In fact, many of the worst religion practitioners actively exploit that lack of self-correction in their own benefit.

    • I would also argue that it wasn't ever really a dogma of chemistry. It was more of a useful approximation.

      Chemists have long known that all the electrons contribute in some way to interactions. However it is a very useful approximation to say that only the outer electrons contribute significantly to bonding interactions. The fact is that they greatly dominate all such interactions, making the approximation useful both conceptually and computationally.

      But, we all know that strictly when two atoms interact it

    • Re: (Score:3, Informative)

      by Vornzog ( 409419 )

      'Dogma' is common in the sciences, but it implies something different than the formal definition you are thinking of. It is usually used to describe a highly simplified model of how a system works. It's just a useful way to think about something.

      The most well known example is the central dogma of molecular biology [wikipedia.org]. By the time you finish freshman molecular biology in college, you know that it is a gross simplification of how a cell works, but that it is a very good first approximation.

      Chemistry is no dif

      • by philspear ( 1142299 ) on Saturday August 02, 2008 @01:47PM (#24449105)

        Indeed, there are several dogmas of science, and they are each found to be violated after a few years.

        On the central dogma of molecular biology for example, the dogma holds that DNA is transcribed into RNA, which is then translated into protein.

        With retrovirus though, it goes RNA--> DNA --> RNA --> protein, which is the most blatant violation. Regulatory RNA mollecules also violate the dogma, showing that whole protein step is non-essential.

        Given the traditional definition of dogma as something that is inflexible to the point of causing violence, I think it's good that science has started to co-opt it and prove concretely that dogmas can be violated without the general veracity of them falling apart.

        Maybe religions will take note. "Hey, the central dogma of mobio has some exceptions but still DNA gets turned into RNA and then gets turned into protein. Maybe if we admit the bread doesn't ACTUALLY become flesh, we won't all go to hell?"

        Yeah, crazy thoughts that will probably get me burned at the stake.

        • by ceoyoyo ( 59147 )

          I really don't understand the modern penchant for changing the meaning of a word to affect change in society. Perhaps, rather than changing the meaning of dogma and having to invent another word to mean inflexible belief, we should encourage people to honesty give up tightly held dogmas.

    • I don't think it's necessarily an altogether inaccurate characterization of the way some scientists can behave towards colleagues. Highly surprising new discoveries are often treated with enormous skepticism by scientists until they are independently confirmed (theory) or reproduced (experiments). The researchers behind highly surprising new results will meet all sorts of reactions that can vary from keen interest, respect, healthy skepticism, disbelief, rejection, ridicule, pillorying, to withholding of fu
    • No, it's the difference between science and human nature. Like or or not, we evolved [or were designed, whatever] to be dogmatic. It's a very important survival mechanism. Human beings hate change, hate it with a passion. One of the big ideas in science is the idea that knowledge can change. But even in science, the general attitude is that there is a static unchanging set of truths that the scientific method is slowly approaching.

    • by ceoyoyo ( 59147 )

      I wonder how the priests of chemistry would punish heretics? A sodium hydroxide bath at the stake?

    • Yes, these were chemists. Chemists aren't exactly dogmatic. They are real scientists. It's not like they're biologists...ick

    • by jav1231 ( 539129 ) on Saturday August 02, 2008 @02:37PM (#24449571)
      Injecting some snide comment about religion into every science story on /. is getting about as bad as injecting "Bush" into...well, every other story on here. Dude, if you wanna beat-off guilt free just do it!
    • Actually, religion just demands religious new information. If God comes down and says that giant worms live in the Earth's core everyone will believe Him.

    • by chill ( 34294 )

      Unfortunately, we can't blame this one on ./ editors.

      From the article:

      The phrase "core chemistry" is taking on a meaning that's definitely not mentioned in the standard curriculum, and which in fact goes against chemistry dogma.

    • Re: (Score:3, Interesting)

      Not to mention that any 2nd year Chemistry student will tell you that it was never dogma. The reason why they don't consider the "interior" electrons is because analytical solutions are... difficult and there influence is negligible. So, they ignore the effects because it doesn't effect the outcome.

      (Aside: Engineers do the same thing. If you saw the math that they use, they regularly assume that series converge and chop off all but a few terms because it won't change the outcome in context.)

      Continuing, t

  • arXiv link (Score:5, Informative)

    by Hal-9001 ( 43188 ) on Saturday August 02, 2008 @01:00PM (#24448671) Homepage Journal

    For anyone who wants to read the actual paper: http://arxiv.org/abs/0805.2781 [arxiv.org]

  • by FST ( 766202 ) on Saturday August 02, 2008 @01:01PM (#24448679) Journal
    Just because an electron is in the outer "core" doesn't mean it's a valence electron. Similarly, the converse is also true. As IUPAC put it, the number of valence electrons is equal to "the maximum number of univalent atoms (originally hydrogen or chlorine atoms) that may combine with an atom of the element under consideration, or with a fragment, or for which an atom of this element can be substituted." This still holds true for the interactions in question in TFA.
  • Thats why (Score:3, Funny)

    by eille-la ( 600064 ) on Saturday August 02, 2008 @01:03PM (#24448701)

    Aahhh, that's why all the experiments I made while standing in the center of the earth sometime failed!

  • This is fascinating. I know it is all very theoretical, and based on computer models of how a material behaves under extreme pressure.

    But frankly, I fail to see any practical applications for this. We are talking about 1,5 million atmospheres and 3000 Kelvin - hence not a typical lab environment.

    But I will with no doubt be proven wrong in the following years. That is why following science is so fun at times :-)

    • by jeiler ( 1106393 )

      But frankly, I fail to see any practical applications for this.

      Like you, I can't see any practical applications. But the science itself is fascinating.

      It does make a certain measure of sense (to my no-more-pure-sciences-since-high-school mind): the additional energy provided by the heat and pressure would excite all of the shell layers.

      But I confess I'm over my depth: I go more towards computer sciences than physics.

    • Doesn't seem surprising to me in the least. Given enough pressure and heat, not only do the inner electrons start to interact, but so do the nuclei. This is called fusion. I'm not a particle physicist, but it seems to be mostly related. As you increase the amount of heat and pressure, and therefore increase the energy acting on the particles, the particles that under normal lab conditions usually wouldn't interact, because of insufficient energy to be moved, are now completely able to participate in a r
      • by dk90406 ( 797452 )
        Doesn't seem surprising to me in the least. Given enough pressure and heat, not only do the inner electrons start to interact, but so do the nuclei. This is called fusion.

        Not quite the same. Fusion is when the atom core (protons/neutrons) melts together with another atom core. Here we are talking about the electrons in the inner shell interacting.

        But in a way you are right, TFA describes the atoms being in a state that the electron in the outer shell is stripped from all atoms so all atoms are ions, and

    • by rde ( 17364 )

      This is fascinating. I know it is all very theoretical, and based on computer models of how a material behaves under extreme pressure.

      But frankly, I fail to see any practical applications for this. We are talking about 1,5 million atmospheres and 3000 Kelvin - hence not a typical lab environment.

      The point isn't that they act differently under high pressure; it's that they act differently. Whenever we've got a model that's proved wrong - and it happens all the time - then new theories come forward to explain

    • by ceoyoyo ( 59147 )

      There's lots of interest in exploiting unusual states of matter on small scales. You could cage a bit of this lithium compound in a buckyball or other matrix, for example.

  • by Cadallin ( 863437 ) on Saturday August 02, 2008 @01:09PM (#24448761)
    Standard for "Science Journalism." The result is actually far less earth-shattering than the author is trying to portray. Researchers think they have found a set of conditions in which the usual models used in chemistry don't apply anymore.

    Now that's a fucking shocker. Most Chemistry today focuses on conditions either similar to STP or than can be created within STP. STP is "Standard Temperature and Pressure" Usually defined for the purpose of convenience of communication as 298K and 760 Torr. They define this as "standard" because everybody in Chemistry knows that chemistry changes as you change conditions, and it's useful to have a standard to compare to, even an arbitrary one (298K, 760 Torr is "average" sea level temperature and air pressure). The standard is also very useful for Chemical Engineering.

    The article is poorly written garbage.

  • by MagusSlurpy ( 592575 ) on Saturday August 02, 2008 @01:15PM (#24448819) Homepage
    High-pressure reactions are an almost completely unexplored aspect of chemistry; and the research that has been done shows that atoms and molecules behave much differently under high pressures. For example, a lot of research is being done now utilizing ultra-high pressure water as a replacement for organic solvents, for greener chemistry. If there's one thing we've learned from these high-pressure experiments, it's that everything acts different, so it really doesn't go against our "dogma" at all; it just goes against the "dogma" of STP reactions, which makes sense, as this was not an STP reaction. It's an incredibly cool finding; just not something that's going to turn all of our current chemical understanding upside down by violating "dogma."
    • by JustinOpinion ( 1246824 ) on Saturday August 02, 2008 @01:36PM (#24449011)

      For example, a lot of research is being done now utilizing ultra-high pressure water as a replacement for organic solvents, for greener chemistry.

      I think you mean ultra-high pressure carbon dioxide, not water. Supercritical CO2 [wikipedia.org] is indeed an interesting area of research, as it can be used to replace dangerous organic solvents, making industrial chemistry safer and greener.

      And I agree that there is likely a rich unexplored landscape of interesting chemistry beyond standard temperatures and pressures.

  • core correlation (Score:5, Informative)

    by rangek ( 16645 ) on Saturday August 02, 2008 @01:26PM (#24448911)

    Chemists already know that core electrons do influence bonding and such. It is simply a short cut to ignore them. Hence, when one wants to get the last few digits on your answer you turn on "core correlation" which treats the core and valance regions the same.

    Furthermore, the conditions in question here are so extreme as to border on being a plasma or some such. So I am not really surprised to see some effect that are negligible under "normal" conditions to grow and become important.

  • by shadowofwind ( 1209890 ) on Saturday August 02, 2008 @01:45PM (#24449093)

    was any 'dogma' really overturned? My understanding was always that the basic chemical rules were first order approximations, not a comprehensive description of how everything must behave. For example, xenon is an 'inert' element, with the outer shell full, but xenon tetra-fluoride (XeF4) is a stable compound. I learned that in high-school in the 1980's.

  • Not news. (Score:4, Insightful)

    by FlyingBishop ( 1293238 ) on Saturday August 02, 2008 @02:04PM (#24449285)

    Chemistry's rules exist because they functionally explain chemistry in an accessible manner. Physicists have known that there are more accurate models for a while. Unfortunately, these models are too complex to be useful to someone trying to synthesize a chemical. If this has any significant applications, we will still be seeing classical chemistry for at least a century to come (barring the singularity.)

    I mean, it's been almost a century since relativity and quantum mechanics came on the scene, but for the majority of engineering tasks, they remain useless. Between processors hitting the atomic scale and more probes hitting the atmosphere, that may change. However, I don't see chemistry getting to the point where we even begin to see practical chemistry that doesn't rely on classical models. The new ones are simply to complex to use.

  • Lithium... (Score:2, Informative)

    Let's not forget that Lithium only has 3 electrons, 2s1 and 1s2. With this is mind it's not all that surprising.

  • by Graff ( 532189 ) on Saturday August 02, 2008 @02:15PM (#24449369)

    IAAC (I am a chemist)

    Honestly this result is not unexpected. The interactions of electrons and nuclei depend on several factors: distance, energy, and charge. There is also the factor of election-electron interaction, which is where the idea of valence electrons comes about.

    Normally the outermost electrons of an atom are far enough from the nucleus that the distance from the nucleus and the repulsion from the other electrons on the atom allows them to more easily interact with other atoms. This is how bonding works, an electron gets "shared" between two atoms or the electron completely jumps off the atom and turns the atom into an ion which is attracted to other, oppositely charged, ions. Yes, I'm oversimplifying quite a bit for the layman.

    Every electron in an atom can interact with another atom, it's just MUCH less likely to happen for the inner electrons of an atom and the interactions of the inner electrons to other atoms are much weaker than those of the outer electrons. Increasing the pressure allows the inner electrons to interact more strongly with other atoms.

    Under higher pressures and energies two things happen. First of all atoms are pressed closer to each other. This means that all of the electrons are closer to other atoms. This increases the likelihood that an electron will interact with another atom, forming a bond. The second effect is that the increased energy tends to cause the electrons in atoms to jump to higher energy states which are further out from that atom's nucleus. This means less crowding which means less repulsion from other electrons which means that each atom's nucleus is more exposed to interaction with other atom's electrons. Again, I'm oversimplifying for the layman.

    The extreme of this is when the pressure is great enough that each nucleus gets close enough for the nuclear force to overcome the electrostatic repelling force between the two positively charged nuclei. When this happens you get neutronium, the core of a neutron star. Obviously you don't normally see these levels of pressure on Earth!

    What is really in question is the exact numbers of the interactions. At what pressure does a certain phase of atom to atom interaction appear? How does the increased pressure affect rates of reactions between atoms? Scientists are trying to measure hard numbers of the effects of pressure on chemistry. There already is a good deal of theoretical work but the experimental work is a bit tough to do given the conditions needed.

    • Re: (Score:3, Funny)

      by Graff ( 532189 )

      Man I hate it when you re-read something you wrote and find stupid little errors:

      There is also the factor of election-electron interaction

      Apparently I have the upcoming presidential election on my mind too much these days, it's even starting to creep into my chemistry...

      Of course I meant electRon-electron interaction, not electIon-electron interaction. Still, I'm pretty sure that electrons will be vitally important in the upcoming elections!

  • by Anonymous Coward

    "Researchers have found that the long-held belief that only the outer, valence, electrons of an atom interact may be false.

    Take Chemistry 101 and 102 in a college today. They no longer believe this. Though I guess it is unusual for lithium. However the center of the Earth is as hot as surface of the sun, and is essentially a ball of plasma, which is so hot nucleons congregate together and all the electrons dance around it.

  • That's nice. Science is fun. But since when would we ever find Lithium at the Earth's core? When would Lithium ever come under such pressure? The only Lithium that matters to me is the stuff IN MY VEINS...

    RS

  • dogma ??!! (Score:3, Interesting)

    by bindo ( 82607 ) on Saturday August 02, 2008 @08:06PM (#24451713)

    fuck! the editor uses the word Dogma and everybofy goes ballistic with politics, philosophy, science, the electric universe ....

    gee what a succesful troll.

    Shit! if things continue to get this bad I will have to RTFA just to have some insight on the lithium thing ...

    relax

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