Slashdot is powered by your submissions, so send in your scoop


Forgot your password?

Thin Water Acts Like a Solid 138

Roland Piquepaille writes "What happens when you compress water in a nano-sized space? According to Georgia Tech physicists, water starts to behave like a solid. "The confined water film behaves like a solid in the vertical direction by forming layers parallel to the confining surface, while maintaining it's liquidity in the horizontal direction where it can flow out," said one of the researchers. "Water is a wonderful lubricant, but it flows too easily for many applications. At the one nanometer scale, water is a viscous fluid and could be a much better lubricant," added another one."
This discussion has been archived. No new comments can be posted.

Thin Water Acts Like a Solid

Comments Filter:
  • by Anonymous Coward on Wednesday April 25, 2007 @03:20PM (#18875285)
    Well, based on poor results getting it on in a swimmin pool, I can verify that water is a lousy lubricant at normal scale!
  • by Anonymous Coward
    Here's an microscope []. On behalf of everybody on slashdot, we're going to use atomic force. In deference to your occasional useful post, we're going to allow you a thin layer of water as a lubricant.
  • by gillbates ( 106458 ) on Wednesday April 25, 2007 @03:25PM (#18875375) Homepage Journal

    But cold water also acts like a solid at times.

  • Canadians and those from other northen countries let out an audible "DUH!" when reading a Slashdot article that stated that solid water is slippery. Speed skaters everywhere found rolling on the floor in hystarics.

    more at 6:00
    • Re: (Score:3, Informative)

      by Anonymous Coward
      Well, you're partially right. The liquid water on frozen water is indeed very slippery. This is what allows ice skaters to skate, the blade glides along a thin film of liquid water. Frozen water on its own, however is not that slick.
    • Duh, Roland (Score:4, Interesting)

      by iamlucky13 ( 795185 ) on Wednesday April 25, 2007 @04:43PM (#18876513)
      Density and viscosity are the primary factors when choosing a lubricant. Water happens to have a pretty low viscosity. The point of article is that the effective viscosity increases by several orders of magnitude in truely thin sheets and takes an ordered form like a solid in one direction but not the others, not that thicker films of water can be used as a lubricant. In fact, they found that as the gap gets down to a nanometer, it becomes a less effective lubricant.

      I started typing this and thought to myself, "Something about the way that submission is written and how it misses the point of the article smells of Roland Piquepaille."

      I wasn't at all surprised when I went back and checked the author to see his name and standard question-link-quote writing format.

      Now I'm curious because the pressure they apply seems to be of interest here. I'm curious if 3 dimensional order appears under high isotropic pressures. If so, I'd expect this to be possible in larger volumes with sufficient pressure, and I wouldn't be at all surprised if the viscosity increased, too.
      • Re: (Score:2, Informative)

        by snoop.daub ( 1093313 )
        Yes, liquid water under pressure at room temperature will indeed solidify. You need a hell of a lot of pressure, and the crystal form will be one of the other 12 known forms of ice, not the familiar ice(I) we know and love. In this case, it's actually ice(VII), a high pressure form consisting of two interpenetrating cubic lattices. The interpenetrating lattices allow more water to squeeze into a smaller space than in the liquid. Water is a truly unique substance, from a physical chemistry standpoint. I
    • Re: (Score:2, Informative)

      by AikonMGB ( 1013995 )

      If I'm not mistake, solid water isn't actually slipper in and of itself.. its the thin layer of liquid water we create whenever touching it and applying pressure. Look up curling [].

      Of course I'm open to enlightenment if I've got something wrong.


  • by kansei ( 731975 ) on Wednesday April 25, 2007 @03:29PM (#18875451)'s called prison lube.
  • What I want to know is: can the layers be manipulated individually? If so, then that shows promise for nano-scale, water-based logic circuitry. Such "circuitry" could continue to function in the event of severe EMP event, such as in a nuclear attack. Promising.
  • by cyfer2000 ( 548592 ) on Wednesday April 25, 2007 @03:40PM (#18875611) Journal
    If it is hydrophobic, what we see may actually be the effect of lost entropy due to rearrangement of water molecules, rather than compression.
    • by snoop.daub ( 1093313 ) on Wednesday April 25, 2007 @04:23PM (#18876277)
      This is a hydrophilic channel. In a hydrophobic channel, the vapor phase is more stable than the liquid, so you get "cavitation" or "dewetting", as you approach the walls of the channel closer and closer, at some point all the water gets pushed out of the channel and the walls get pushed together.

      The phenomenon is well understood in the hydrophobic case, both experimentally and in simulations. This experiment is new, up till now they couldn't get down to such small separations, but they are overstating the case when they claim that this is a complete surprise... as another poster said, many many simulation studies have suggested a structuring of water near hydrophilic surfaces.

      Another neat thing happens when you have one wall hydrophobic and one wall hydrophilic. This has been dubbed a "Janus interface" after the two-faced Roman god, and there's a lot of interest in them.
    • by cyfer2000 ( 548592 ) on Wednesday April 25, 2007 @04:47PM (#18876575) Journal

      OK, I read the paper, DOI: 10.1103/PhysRevB.75.115415.

      They did experiment with a Molecular Iamge PicoPlus AFM with the funny sound proof box and rubber bands, if you saw such a system you will know what I mean. The tip they used had a stiff cantilever and was "likely to be oxidized". They carefully controlled the sample surface and make it perpendicular to the tip. And they did the experiment on three surface, mica, soda lime untreated glass and highly oriented hydrophobic graphite.

      And the result is hydrophilic surfaces showed increased viscosity and the hydrophobic surface showed no change.

  • by kebes ( 861706 ) on Wednesday April 25, 2007 @03:42PM (#18875663) Journal
    There's actually alot of evidence in the literature suggesting that water forms a "structured layer" on hydrophillic (water-compatible) surfaces, and around hydrophillic objects dispersed in water. For instance the mobility of water that structures around proteins has been described in the literature as "ice-like." These measurements are typically based on the density of the water or using things like conductivity to infer mobility.

    So the notion of water forming solid-like structures near surfaces is not entirely new. However, direct mechanical measurements of the mobility/viscosity of those last few atomic layers of water are not easy, so this paper certainly adds a valuable contribution to the field.

    The actual scientific paper in question can be found here: []
    • by kebes ( 861706 ) on Wednesday April 25, 2007 @04:27PM (#18876323) Journal
      For anyone interested, the figures in the paper show clearly the structuring of water in layers near the surface. Moreover they directly measure that the viscosity jumps up considerably for distances less than 2 nm. The viscosity goes from the bulk water value (9E-4 Pa*s) when far from the surface, and increases to as high as 50 Pa*s (500 Poise or 50,000 cP) in the last 0.5 nm. To give you an rough idea of what this means, note that 50,000 cP is similar to the (bulk) viscosity of things like honey or ketchup (for a random table of values, see here [] or here []).

      Of course this higher-viscosity persists only over a very short-range, but understanding these "nano-mechanical" properties is crucial for the design and construction of future nano-scale devices.
  • by cdogbert ( 964753 ) on Wednesday April 25, 2007 @03:43PM (#18875667)
    From what I can tell, F@H touched on this [] a while ago. I was reading the PS3 F@H articles, browsing through the "what good does F@H do?" and the "F@H is just a feel-good project" comments and looking at the results page [] when I stumbled across the above PDF and thought "Hey, that looks like something slashdot just reported on."
  • by WED Fan ( 911325 ) <.ten.liamhsart. .ta. .egihaka.> on Wednesday April 25, 2007 @03:47PM (#18875735) Homepage Journal

    "What happens when you compress water in a nano-sized space? According to Georgia Tech physicists, water starts to behave like a solid.

    Alright, you know, if you had asked me this question, way back when, I would have said it acts like a solid. Why is this news, am I missing something?

    • by mstahl ( 701501 ) <> on Wednesday April 25, 2007 @04:26PM (#18876311) Homepage Journal

      Oh my god I can't believe I actually read that as "I Am Not A Scientist But I Play One On TV". . . .

      Be back soon guys . . . I'm gonna go outside for a while.

    • i can't imagine how many resources we waste every year researching and demonstrating things that we would have known for free had we just asked you "way back when". actually, i imagine if i just ask you how much we'd save with this method that'd be easier than trying to calculate it
      • Re: (Score:1, Offtopic)

        by WED Fan ( 911325 )
        What happens when you compress something? It becomes more dense. As something becomes more dense it starts to approach the solid. Solid is typically more hard. Granted, it may have taken a scientist with resources to figure out what all the properties and reactions were, but as for "Water gets more solid as it is compressed", DUH.
        • Re: (Score:3, Informative)

          by Pollardito ( 781263 )
          well, my reply was just me teasing, but the thing that makes this unintuitive is that water as a solid is not more dense, so one wouldn't necessarily expect water that's been condensed to act like solid water, and as a matter of fact there had been studies that it didn't :

          In its bulk liquid form, water is a disordered medium that flows very readily. When most substances are compressed into a solid, their density increases. But water is different; when it becomes ice, it becomes less dense. For this reason,

  • "water is a wonderful lubricant" ok i'll remember that next time i'm with my girlfriend :P
  • by infosystech ( 1093309 ) on Wednesday April 25, 2007 @04:09PM (#18876071)
    How about just outside the Gatlinburg museum's entrance, visitors can see a 5-ton solid granite ball floating and spinning on 1/264 of an inch of pressurized water. Visitors may put their hands on the 4-foot diameter ball and spin it in another direction. Or the Merchant Family Memorial (Ripley's Believe It or Not Ball).
  • If you have ever gotten laid, like me - you would know that waterbased lubricants are great for carnal pleasures. Just watch Talk Sex with that canadian chick on the show. She's always babbling about how waterbased lubricants are the way to go. They help a lot. They prevent a condom from tearing, and they should be used if you're going in 'the other door'.

    Back on topic, will this 'discovery' in nanobased water lubricant be functional in almost all applications? I mean, you can't use this in a system that wi

    • Petroleum based lubricants last much longer than water based, under continuous usage.

      Oh... you hadn't discovered that... so sorry.

      • right on dude. plus, petroleum based lubricants are also better conductors of heat, in case you've noticed.
      • That may be, but you'll find your condom doesn't last quite so long as the lubricant.
      • Re: (Score:2, Informative)

        Yep..Oil/petroleum-based lubricants have been proven to deteriorate the latex in the condom and aren't safe at all, fyi.
        • Re: (Score:3, Interesting)

          by xtal ( 49134 )
          Polyurethane condoms are not affected by oil based lubricants.

          • Polyurethane condoms are not affected by oil based lubricants.
            True, but they also aren't as flexible, soft and elastic.
    • Re: (Score:3, Informative)

      by treeves ( 963993 )
      Water != water-based. Typically water-based includes glycerin, polyethylene glycol, or other substances. The viscosity of pure water is much lower than that of water-based lubricants.
  • by IceCreamGuy ( 904648 ) on Wednesday April 25, 2007 @04:18PM (#18876207) Homepage

    Contrary to popular belief, water organizes into layers when compressed into a nano-sized channel.

    I can't believe the popular notions of water in a nano-sized channel are false! Soon they'll be saying that the attorney general acts like a solid under pressure in a nano-sized tube. If we can't believe the popular notions of nano-tube water behavior, what can we believe? My life is a lie!
  • An element acting like a solid!! Whoever would have thought it?

    Someone should have saved them some time and just told them to pop it in the freezer :P

  • by k3v0 ( 592611 ) on Wednesday April 25, 2007 @04:51PM (#18876655) Journal
    sounds like Ice 9 to me

  • Never have I ever heard such utter rubbish. These people really should get out more and get a grip on reality.
  • by wisebabo ( 638845 ) on Wednesday April 25, 2007 @05:32PM (#18877325) Journal
    In Arthur C. Clarke's book "The City and the Stars" later re-released as 'Against the fall of Night", it mentions a slidewalk which was a solid in one dimension but a liquid in the other two. That way, you could walk onto the middle portion and be carried along by the "current" while standing. Still what do expect from a civilization a billion or two years in the future?

    Grew up on his science fiction and fact books; "The Promise of Space" was seminal to my interest in space. Unfortunately his (alleged) personal discretions have cast a serious shadow over his legacy.
  • "At the one nanometer scale, water is a viscous fluid and could be a much better lubricant," added another one.""

    Oh good I was wondering when KY could finally enter into the water market.
  • Not just old, but ancient news. Jesus showed that effect almost two millennia ago. :p
  • The properties of liquids in bulk have been known to be considerably different than otherwise restricted states (films on surfaces, surface of bulk, capillary properties, adsorbed liquids, etc.) Water is strongly affected due to strong hydrogen bonding in addition to dipole forces. So what's new here?
  • Thin water. Soon to be all the rage of nutty health food people who claim to be so smart, yet are stupid enough to shell out $2.50 for something that is less healthful than water they can get for free.


    Science project, or clever marketing campaign? :-)
  • This was a pretty obvious conclusion. If you compress water (or anything), then you reduce the amount of space that molecules have to move around. When you compress it to the point that the water molecules are only allowed to vibrate in the same amount of space that they do in a solid, then you have, in effect, created a solid. Even though water molecules are in a crystal lattice when they are in a solid state, they still vibrate.

    If you compress liquid water to a density of 0.92 g/cm, then it is no suprise
    • If you compress liquid water to a density of 0.92 g/cm, then it is no suprise that it will act like a solid.
      Except of course, that the normal density of water is 1 g/cm^3. And increasing the pressure tends to compress stuff, i.e. raise it's density. So you can't get water to a density of .92 g/cm^3 by simply compressing it.

  • Each of our cells are huge nanoscale factories that use water as lubricant. What these scientists are doing is reinventing the wheel.
  • ...water is a viscous fluid and could work as a lubricant. Gee. Ya think? I wonder if that's why most living things on Earth are made of... wait for it... WATER! Duh!!! Now let me get back to my project to create snapshot backups of the quantum structure of the universe for disaster recovery before the boss... er... wife gets back. Geez, someone told me Slashdot was the place for geeks. You guys are bush league. - Magrathean Planet Builder
  • Stuff like this is what "nano" is actually about. These guys are probing a layer of water so thin that it is almost all surface, so it doesn't exhibit water's "bulk" behavior.

    Think of it this way: In bulk liquid form, almost every molecule of water is surrounded by other water molecules, like in a glass of water. But, if you create a layer of water so thin that most of the molecules do not neighbor water molecules, and instead neighbor other things like a surface or their "tip," new behaviors can be ob
  • I know I'm being sarcastic and sophomoric, here, but jesus. Why is it news to anyone, especially scientists, that if you compress a liquid as far as it'll compress it won't compress any more? I mean, this is a scientific "breakthrough" Yogi Berra could have told you.
  • by timias1 ( 1063832 )
    Otherwise I might try high diving into a glass of water only a few nanometers deep
  • Wikipedia indicates [] that this is *very* old news ...

    The author Vonnegut credits the invention of ice-nine to Irving Langmuir, who pioneered the study of thin films and interfaces. While working in the public relations office at General Electric, Vonnegut came across a story of how Langmuir, who won the 1932 Nobel Prize for his work at General Electric, was charged with the responsibility of entertaining the author H.G. Wells, who was visiting the company in the early 1930's. Langmuir is said to have come up

I bet the human brain is a kludge. -- Marvin Minsky