New Results Contradict Long-Held Chemistry Dogma

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."

Comments

Poor choice of words

[Angst Badger]

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.

Re:Poor choice of words

[LaskoVortex]

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

Re:Poor choice of words

[Adambomb]

Scientific theories only hold out until something else comes along with more facts that change our understanding

Right. That's called the scientific method.

It's kinda the whole point. Do what you can with what you have where you are, and when you find out how you're wrong you adapt.

Re:Poor choice of words

[Anonymous Coward]

500+ years ago scientists thought the earth was flat.

No, they really didn't. Hell, over 2000 years ago the Greeks already knew the Earth was a sphere. They even knew its diameter! The idea that everyone ever thought the world was flat is entirely false - go ready a history book and stop perpetuating such garbage.

Re:Poor choice of words

[rangek]

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.

Re:Poor choice of words

[RzUpAnmsCwrds]

500+ years ago scientists thought the earth was flat.

No, they didn't. It's called the flat earth myth.

Scientific theories only hold out until something else comes along with more facts that change our understanding.

Uh, yeah? That's the whole point of Science. Scientists try to create theories that best fit the available data. More importantly, they are always looking for new evidence which will either corroborate or contradict their theories.

Re:Poor choice of words

[Vellmont]

Really? For science I rather find the more we understand, the more we realize we don't understand.

This is true. But this also increases our understanding, not decreases it. known unknowns > unknown unknowns.

Scientific theories only hold out until something else comes along with more facts that change our understanding.

To a degree, yes. But a new theory doesn't usually completely obviate the old one. Newtons F=MA still works for the vast majority of the time for things us humans are likely to come into contact with, it just begins to break down as you approach the speed of light. Special relativity only becomes relevant in special cases.

Re:Poor choice of words

[xZgf6xHx2uhoAj9D]

The knowledge wasn't forgotten. Columbus was the exception, not the rule. Everyone was telling him "Columbus, you're a dumbass. India's at least twice as far away as you think it is". You can't blame an entire time period for Columbus' fortuitous stupidity.

Re:Poor choice of words

[ericferris]

Good points. You don't really have "dogmas" in science, just hypotheses and results that you better not question because then you might piss off someone, lose you grants and be blackballed in peer reviews.

Sadly, the peer review system does not shield scientists from flaring egos and grant sucking. It's a great system where it works, and surely beats the old ways of taunting competitors with results they couldn't reproduce as was the case during the Renaissance. But it still breaks sometimes when seniority, ego and money are involved.

And of course, politics now play a role. Take something that should be as neutral as cosmology, namely, climate study. Now it's tainted with politics. That's rather disquieting.

The motto of the Royal Society -- the 500-year old British academy of sciences -- is "Nullius in Verba", meaning you are not compelled by the word of someone else, only by truth. I wish it were the case.

Re:Poor choice of words

[SEE]

It wasn't forgotten. The reason Columbus had so much trouble getting funding was that the royal courts of the time hadn't forgotten; they used Eratosthenes' old number (confirmed by the astrolabe), and then accepted Ptolemy's assessment that it was 180 degrees from one end of Europe to the opposite end of Asia. They knew there was no way that Columbus could reach Japan from the Canaries, 12,000 miles away, without running out of water (no ship of the era was big enough to carry enough for a trip of that length). So advised against giving him money, no matter how much Columbus insisted it was only 2,300. As it was, the reason why the terms of his contract with Fredinand & Isabella was so generous is that everyone expected him to die on the trip rather than make landfall.

And Columbus wasn't ignorant of Eratosthenes' number and Ptolemy's estimate; it was simply that he reached his error based on a different set of authorities:

1) That of Marinus of Tyre (from the first century AD), who thought that Eurasia was 235 degrees in width instead of about 180.
2) The measurement of Alfraganus that underestimated the size of a degree somewhat.
3) His own mistake of assuming that Alfraganus's mile was the same length as an Italian mile (which were 2/3rd the size).

Based on those numbers, it was perfectly reasonable to believe he'd reached Asia.

Re:Poor choice of words

[The Wannabe King]

The knowledge that the earth was round lasted through the dark ages too. When Columbus was laughed at by the church' experts, they didn't point out that the world was flat, but that Columbus used a too small value for the circumference of the earth. Therefore he would starve to death before reaching Asia. They were right, Columbus was just very lucky to hit America before it happened.

Generally, the dark ages weren't nearly as dark as historians from the 19th century depicted it to be.

Re:Poor choice of words

[William Ager]

Oh dear... as someone said already, I expect this is probably an electric universe rant, and that responding to it will do almost nothing. I could moderate it down, but other mods probably wouldn't understand my reasons for doing so, as the parent avoided mentioning the crackpot theory itself.

It should be said, however, that the odd thing about the dark matter predictions are that they work very well, as do the dark energy predictions. We did many have other models that were put forward, some containing significant changes to various theories. None of them worked nearly as well as our current model with dark matter. There are many people in the community that don't like our lack of knowledge about dark matter, but it works so well that, as with many things in high energy physics, we can only assume that it is actually there until we come up with a better theory.

As for black holes, I would suggest that you actually learn modern GR before suggesting that you understand the theory better than everyone else in the community does. In fact, try learning real cosmology, and looking at results like measurements of CMB anisotropy, and Big Bang nucleosynthesis.

arXiv link

[Hal-9001]

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

Valence != Outer Core

[FST]

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.

Sensationalist Bullshit.

[Cadallin]

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.

Goes against chemistry dogma?

[MagusSlurpy]

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."

Re:Goes against chemistry dogma?

[JustinOpinion]

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 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

[rangek]

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.

Re:Thats why

[ScrewMaster]

No, they failed because, as everyone knows, the center of the Earth is actually hollow, contains a breathable atmosphere, and is full of prehistoric creatures.

Re:Of course!

[4D6963]

Computer simulations?

You mean like the computer simulations that say the earth is warming? Hahahaha...

Indeed. Between your intuition and computer simulations running on super-computers based on decades of research on predictive models designed by the most competent and dedicated researchers in the domain, always trust your intuition.

This is why I never watch the weather channel, I just look at how leaves move in the wind, how menacing clouds look, then I wet my pointer finger, put it in the air and I can tell you how the weather will be tomorrow. Well I can tell what it will be, doesn't mean I turn out to be right, but hey, the Weather Channel is wrong sometimes too!

Interesting results, but

[shadowofwind]

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.

"It leans far left and toward science"

[MillionthMonkey]

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?

Electron-Nucleus Interactions

[Graff]

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:Proof that Proof isn't Always Right

[plasmacutter]

For instance, you can scientifically prove that God doesn't exist all you want given the small amount of information we know about our universe.

well, we know where you get your bias against science.

Science tries to prove testable positives. You know a theory is "wrong" if the observations don't match the hypothesis. Even then, it doesn't necessarily mean the theory must be completely disregarded (example: newtonian and quantum mechanics coexist today).

You can't "disprove" god with science because god is not rationally testable. You can't "prove" it either because of that, though, and as such no man of science will accept "the will of god" as an explanation for something, or a reason to perform/avoid certain actions.