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Science

Water Suddenly Becomes Mysterious 76

Posted by timothy from the good-reason-to-stick-with-juice dept.
An anonymous reader writes "Logical to assume that scientists know the structure of water. But wrong. A study in April by Anders Nilsson from the Stanford Linear Accelerator Center concluded the molecular bonds are looser than thought. Now a new study by Richard Saykally's group at UC Berkeley appears to debunk the April results. So a new debate is born. Both scientists agree on one thing: They don't fully understand how water molecules interact."
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Water Suddenly Becomes Mysterious More

Water Suddenly Becomes Mysterious

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  • "Logical to assume" I guess we know why the reader stayed anonymous.

  • Hmm... (Score:2, Informative)

    by Canar ( 46407 )
    Considering that even fluid dynamics has a hard time making water behave in a way that looks realistic, why is this surprising?

    • Re:Hmm... (Score:3, Informative)

      by Mark of THE CITY ( 97325 )
      Different scale, for one thing...

      Spectroscopists use ultrafast experiments for the same reason photographers use fast flashlamps: to capture the action, unblurred. But the motion of water, one of the most labile molecules around, is too fast, and there is argument (at least there was in the mid-90s, when I was going to seminars) about how meaningful the ball-and-stick models of water clusters were. Was it a real geometry, or an average over the time of the laser pulse? Apparently, arguments continue ove

      • Re:Hmm... (Score:3, Interesting)

        by hankwang ( 413283 ) *
        But the motion of water, one of the most labile molecules around, is too fast, and there is argument (at least there was in the mid-90s, when I was going to seminars) about how meaningful the ball-and-stick models of water clusters were.

        Well, I did my Ph.D. on ultrafast infrared spectroscopy of water between 1997 and 2001 and things have changed since the mid-90s. The dynamics of the hydrogen-bond network in liquid water happens mainly on a timescale of a few picoseconds, which is actually in agreement wit

    • fluid dynamics has a hard time making water behave in a way that looks realistic
      That's a different issue. The properties of water in bulk are very well understood. Fluid dynamics sims are pretty damn accurate and deviations from simulations can largely be explained by measurement error or limits of available compute power.

  • Why so mysterious? Drink it, take a shower, ... (Score:3, Funny)

    by CodeMonkey4Hire ( 773870 ) on Wednesday December 01, 2004 @10:31AM (#10963260)
    Some of the programmers I work with don't understand that water (when used with soap) can help remove that small that follows them around. I wonder if some of these scientists have the same problem.

  • Vodka (Score:2, Funny)

    by Shadow_139 ( 707786 )
    Somebody much of swapped the "control" test with Vodka......

    "NIPPLES!! I HAVE NO NIPPLES!!!" -Happy Noodle Boy

    • Re:Vodka (Score:1)

      by Anonymous Coward
      Not only did you incorrectly use "much" for "must", but you believe the phrase "must of" means something in English.
      The correct phrase would be "must have".

      Perfect Tenses:The perfect tenses show completed state or action.
      The present perfect is formed with has or have and a past participle. (i.e., "Somebody has swapped the 'control' test with vodka.")
      The past perfect, also called the pluperfect, requires had and a past participle. (i.e., "Somebody had swapped the 'control' test with vodka.")
      The future p
    • And another thing - I stopped reading sigs a long time ago, when i realised there was an option to block them, and you just put yours in the text field. I bet you complain about spam as loud as the rest of em, eh? Asshat
  • My cup of tea has suddenlly run off for the weekend with its,..er...well... "friend" and an overnight bag filled with minature chocolate bars, muttering something about Cuba and the mob. Gawd I hope I have the bail money.

  • water is weird (Score:5, Interesting)

    by rritterson ( 588983 ) * on Wednesday December 01, 2004 @10:56AM (#10963491)
    among common substances, water is perhaps the weirdest. Here is why:

    -the solid is less dense than the liquid (ice floats). This is key for life, as otherwise lakes would freeze from the bottom up and freeze solid. The ice that forms on top now acts as an insulator.

    -there are 12 known varieties of ice, depending on pressure and temperature conditiions. Not all of them have a hexagonal crystal strucuture.

    -for it's size, water boils at a very high temperature. This is due to the organization of the liquid into hexagonal rings of 6 molecules, preventing any from evaporating.

    -it's one of the few common substances that we see in all 3 phases. (i.e. you don't see solid vodka around, nor gaseous iron, etc)

    -it's the best known solvent in existance (i.e. it dissolves the most stuff).

    The list goes on and on. Water is actually fairly miraculous.
    • Indeed and it is this weirdness that makes life possible.

      Cheers,

      Roger
    • Why would lakes freezing solid prevent life?

      bacteria survive far harsher environments. Thrive even.

      • It wouldn't.

        But that's because God pointed a finger and said "Let there be Life!"

      • Bacteria are very complex life forms. They may not even have had a chance to evolve in the first place if all the oceans and lakes of the world (1) froze solid every winter, and (2) were permanently frozen beyond a depth of 30 metres or so.
      • Because the liquid water would then serve as an insulator on top of the solid water, rather than the other way around. In most lakes, the solid water at the bottom would never thaw once frozen. The climate would gradually cool; Earth would wind up as an ice planet with a cold climate and narrow water-belt instead of a water planet with a greenhouse climate and two small ice caps.
    • -it's one of the few common substances that we see in all 3 phases. (i.e. you don't see solid vodka around, nor gaseous iron, etc)

      I didn't know vodka was an element now.
    • all of the weird properties can be explained by hydrogen bonding.

    • Re:water is weird (Score:1, Funny)

      by Anonymous Coward
      Um, you missed out the miracles of:

      1. selective parting to separate mutually-hostile people groups

      2. use in cure for leprosy, and other things

      3. instant conversion to grape juice product

      4. unusual pedestrian support
    • -it's the best known solvent in existance (i.e. it dissolves the most stuff).

      This reminds me that it is used in homeopathy. The problem is that it seems the active substance is diluted so much that there is probably not a single molecule of it left in the water. Yet, it works. As far as I know, scientists don't have a clue about how it can work, and many tend to doubt it does. Competent homeopats may have theories about how it works, but these theories never seemed to make much sense to me (they actually
    • you don't see solid vodka around, nor gaseous iron

      "Is not necessaraily true, comrade," said the drunk Siberian, licking his vodka popsicle and squinting at the sun.

    • there are 12 known varieties of ice

      However, it's only the ninth one that's real trouble. Well, unless you believe all the propaganda about DHMO.

  • I'm skeptic (Score:5, Informative)

    by hankwang ( 413283 ) * on Wednesday December 01, 2004 @11:07AM (#10963578) Homepage
    A claim that seems to disagree with everything else that is known should have solid evidence. It is of course possible that these guys are right and that the bookshelves full of other experimental data all are flawed. However, it might also be that the way they measured and modelled ignored some important effect.

    From my background, I can mention that the infrared absorptions of the two OH bonds are at a wavenumber of 3650 and 3750 cm-1 (around 2.7 micrometers wavelength). In liquid water, these absorptions shift to a band around 3400 cm-1 (2.95 micron). It is a widely accepted fact that this shift of the OH vibration frequency occurs as a result of the hydrogen bond forming between the H of the OH and the O of the next water molecule:

    H-OH ... OH2
    There is hardly any absorption in liquid water at 3650 and 3750 cm-1, which would strongly suggest that nearly all water molecules have both of their hydrogen atoms bonded to other water molecules (that means four H-bonds per molecule). If the claim in the article were true, half of the OH groups would be free and absorb at a higher wavenumber.

    The idea that the OH absorption wavelength depends on whether it has a hydrogen bond is in agreement with a large number of studies in which for example clusters of two, three, four water molecules embedded in another material or in vacuum have different infrared absorptions. They are also in agreement with calculations on what happens with an OH bond when you let it form a hydrogen bond, and with fully quantum-mechanical so-called ab initio calculations of how water molecules should behave, although with the latter, one might object that computers still are not powerful enough to do these calculations with more than a couple of ten molecules at a time.

    • A claim that seems to disagree with everything else that is known should have solid evidence.
      Oh... you mean one of the six different kinds of ice?
  • Was the study published 1st April?

    • Huh? (Score:2)

      by troon ( 724114 )

      I've previously noted the phenomenon of comments with similar subjects appearing together chronologically.

      Now we have two comments, both entitled "I'm skeptic", written by different people.

      I'm beginning to think that Slashdot is a huge AI system and I'm the only real person here. I'm also of the opinion that the "A" is far more significant than the "I", especially if the AI code is anything like the "HTML" that Slashcode produces...

  • bit of perspective (Score:5, Interesting)

    by Anonymous Coward on Wednesday December 01, 2004 @01:40PM (#10965220)
    I think most people don't realize that even before these results we didn't have a good grasp of water. This controversy dumps a whole load of new fuel into the large fire. The following issues are more simulation and protein related, but maybe they give brief insight into how much we don't know:

    None of the (molecular dynamics, "MD") computer models of water are currently sufficient to reproduce all of the experimentally observered properties of water. This is a relatively big point of contention when simulating proteins as water needs to be accounted for. There are experimentalists that chide the theorists, even saying that they won't fully believe MD results until a decent model of water has been built. :)

    We also don't quite know what the first hydration shell around a protein looks like. Imagine this is being the closest "coat" of water around a protein. This ordering of water could be a key component to understanding the properties/behavior of protein surfaces in binding to other molecules.

    In addition, water mediated interactions between proteins is almost a completely open question. As far as I know, we don't really know how to approach the problem in an elegant manner and there have been no studies that reasonably address this at a detailed molecular level (partially due to the above two issues) even in a heuristic sense.

    There is a huge literature on water. A good deal of work has been done on the above three issues and other big open issues with water that I won't go into depth on. Needless to say water has been and will continue to be a mystery for quite a while.

    • MOD Parent Up (Score:4, Interesting)

      by exp(pi*sqrt(163)) ( 613870 ) on Wednesday December 01, 2004 @06:02PM (#10968401) Journal
      Hear, hear! Molecular dynamics of large molecules like proteins is complete voodoo, but the emperor isn't listening, nobody wants to believe this. Given the difficulty modeling water any attempt to model a protein (likely surrounded by water) is like trying to fly a jet before you can crawl. I spent a couple of years working with computational chemists. It was astonishing how many tweakable parameters simulations had. There is only one set of laws of physics - there should be nothing to tweak. But computational 'chemists' would tweak and tweak all day. And after the x-ray crystallography results came in they'd say "see, the modeling worked, on the 23rd of last month the sim I ran at 3pm used these parameters and they came out just like these results." The whole area is a joke.

    • "we didn't have a good grasp of water" you said.

      Ever tried nailing water to a tree?

      Your arguments don't hold water. And I'm not getting myself wet by making another counterargument easily liquidated. It's not like drowning in non-solid arguments is going to flow anywhere.

      By the way. Shouldn't the huge litterature "on water" be "underwater"? Some books don't float you know.

      MOD me desinformative. (-;

  • Masaru Emoto (Score:3, Interesting)

    by shpoffo ( 114124 ) <<gro.airdnaxelawen> <ta> <mapson>> on Wednesday December 01, 2004 @03:48PM (#10966927) Homepage
    ...and if there isn't some consideration taken for the work of Masaru Emoto [masaru-emoto.net] then any study is liable to be missing a few hints. He's suggesting that consciousness has a measure effect upon water. In most of the science world, that's Weird Shit, as we can only relate such phenomena to quantum mechanics.

    .
    -shpoffo
  • concluded the molecular bonds are looser than thought.

    Try "previously thought," for example.

    Christ, why do we contine to pay these so-called editors?
    Oh, wait...

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