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IBM Images a Single Molecule

Posted by kdawson on from the blow-it-up dept.

chrb writes "New Scientist is reporting that researchers at IBM Zurich have managed to image a single molecule in detail for the first time. In the images of a pentacene molecule, the bonds between the carbon atoms are visible as five linked rings."

26 of 169 comments (clear)

  1. Cool, but... by sircastor · · Score: 5, Funny

    I guess I expected it to look a little less like a High-school textbook drawing of the bonds. The only thing that would make it moreso is if little Cs were set next to each atom.

    1. Re:Cool, but... by electricprof · · Score: 5, Funny

      The little C's are there, but they are in 0.000000001 font. I think it's Arial.

    2. Re:Cool, but... by marcosdumay · · Score: 4, Informative

      Not exactly. If the electron is bounded, it has some specific momentum probabilities, and some specific position probabilities. You can't find its position with any different certainty unless you remove it from the bounded state.

      And that comes from the uncertainty principle. It is not just Dx * Dp >= h/(2 * pi). It is an statement that each state has some specific uncertanty, and that it isn't lower than that relation.

      --
      Rethinking email
  2. Next story: by Anonymous Coward · · Score: 5, Funny

    Next story: IBM is sued by the IOC.

  3. As expected... by Drakkenmensch · · Score: 4, Funny

    The molecule blinked right when the snapshot was taken.

  4. What Material Is the Pantacene Sitting On? by eldavojohn · · Score: 4, Interesting

    So if the Pantacene is made of Benzene and the Benzene is C6H6, what is that gray flat smooth material that the molecules are sitting on top of in the second picture? Is this simply due to a focus so incredibly tuned that you can't see past the Pentacene molecules? I would expect that to be a field of bumps and crazy random shapes because it has to be made of some molecule or atom, right? How would they finish the slide/table/surface of that so accurately? I'm used to seeing that when you see bacteria or viruses with an electron microscope, what is in effect here that we don't see an alien landscape back-dropping these molecules? I'm not calling into question the authenticity of the image, just curious if anyone knows.

    --
    My work here is dung.
    1. Re:What Material Is the Pantacene Sitting On? by Anonymous Coward · · Score: 5, Informative

      This image isn't from an electron microscope, it uses AFM (atomic force microscopy: http://en.wikipedia.org/wiki/Atomic_force_microscope), which actually touches the molecules with its tip. In this case though, they bonded a single carbon monoxoide molecule to the AFM cantilever so that it would only interact with the oxygen atoms on the pentacene molecule. I imagine it didn't image the substrate at all because of that

    2. Re:What Material Is the Pantacene Sitting On? by mastahYee · · Score: 5, Interesting

      This image isn't from an electron microscope, it uses AFM (atomic force microscopy: http://en.wikipedia.org/wiki/Atomic_force_microscope), which actually touches the molecules with its tip. In this case though, they bonded a single carbon monoxoide molecule to the AFM cantilever so that it would only interact with the oxygen atoms on the pentacene molecule. I imagine it didn't image the substrate at all because of that

      It doesn't actually touch the molecules, because weak force cancels out the attraction. That's kind of a key point here because touching it was too destructive to get these images in the first place.

    3. Re:What Material Is the Pantacene Sitting On? by UnHolier+than+ever · · Score: 5, Interesting

      An AFM image will often look like it has a shadow. In that case, the tip was probably scanning from the right, and it "bounced" after being raised by the pentacene. The shadow size is related to the tip speed as much as the molecule height.

    4. Re:What Material Is the Pantacene Sitting On? by Anonymous Coward · · Score: 5, Informative

      From the Science article http://www.sciencemag.org/cgi/content/full/325/5944/1110 (require subscription):

      " The asymmetry in the molecular imaging in (D) (showing a "shadow" only on the left side of the molecules) is probably caused by asymmetric adsorption geometry of the CO molecule at the tip apex. "

    5. Re:What Material Is the Pantacene Sitting On? by Sorny · · Score: 5, Informative

      You are correct. I get the chance to see AFM readouts at work (you see some really cool shit in a fab), and this is a bit higher resolution that I'm used to seeing, but the "shadow" is something you'll frequently see.

      I've never "seen" the substrate from AFM scans at work either.

      --
      OSX pwns.
    6. Re:What Material Is the Pantacene Sitting On? by MadAnalyst · · Score: 5, Interesting

      A lot of microscopy like this will be done using very carefully prepared atomically smooth surfaces. A good example would be Cu(111). I haven't' dug in, but they might also work with something akin to the "depth of field" in optical work to largely exclude the effect of the background.

    7. Re:What Material Is the Pantacene Sitting On? by Colonel+Korn · · Score: 4, Informative

      So if the Pantacene is made of Benzene and the Benzene is C6H6, what is that gray flat smooth material that the molecules are sitting on top of in the second picture? Is this simply due to a focus so incredibly tuned that you can't see past the Pentacene molecules? I would expect that to be a field of bumps and crazy random shapes because it has to be made of some molecule or atom, right? How would they finish the slide/table/surface of that so accurately? I'm used to seeing that when you see bacteria or viruses with an electron microscope, what is in effect here that we don't see an alien landscape back-dropping these molecules? I'm not calling into question the authenticity of the image, just curious if anyone knows.

      From the paper: "In this work, we present atomically resolved AFM measurements of pentacene both on a Cu(111) substrate and on a NaCl insulating film. For atomic resolution with the AFM, it is necessary to operate in the short-range regime of forces, where chemical interactions give substantial contributions."

      This was a scanning probe microscope, and the tip of the probe was a single carbon monoxide atom. Apparently the CO didn't interact with the Cu or NaCl in such a way that it saw contrast from atom to atom, but it had a finer interaction with the atoms in the pentacene.

      --
      "I zero-index my hamsters" - Willtor (147206)
    8. Re:What Material Is the Pantacene Sitting On? by Colonel+Korn · · Score: 4, Informative

      Sorry to reply to myself, but here's the most important reason for the lack of substrate heterogeneity in the image:

      "The AFM images (Fig. 1, C and D) were recorded in constant-height mode; that is, the tip was scanned without z feedback parallel to the surface while the frequency shift {Delta}f was being recorded (16). In this and all of the following measurements, the tip height z is always given with respect to the STM set point over the substrate."

      In school, when I ran AFM I allow feedback from the tip to adjust the height of the probe so that it maintains contact with the thing I'm imaging, regardless of topography. Here, they had a very smooth substrate and then set the height of their probe to a fixed position above it.

      --
      "I zero-index my hamsters" - Willtor (147206)
    9. Re:What Material Is the Pantacene Sitting On? by je+ne+sais+quoi · · Score: 4, Informative

      Also the physioelectronic structure of the cu(111) is diffuse enough such that you can't easily resolve individual atoms. Each copper atom is so heavily bonded to it's neighbor that there is very little difference from one atom to the next. If you think about it, that makes sense since copper is a conductor, so the electrons must be able to move from one atom to the next easily. Graphite on the other hand (polymerized carbon like the pentacene here) is an insulator -- much less overlap between the orbitals of neighboring atoms.

      --
      Gentlemen! You can't fight in here, this is the war room!
    10. Re:What Material Is the Pantacene Sitting On? by Bob-taro · · Score: 4, Insightful

      It doesn't actually touch the molecules, because weak force cancels out the attraction.

      At this scale the meaning of words like "touch" gets a little fuzzy.

      --
      Prov 9:8 Do not rebuke mockers or they will hate you; rebuke the wise and they will love you.
  5. Re:Molecules are made of atoms, right? by epiphani · · Score: 5, Informative

    Good job reading the article.

    FTA:

    Thanks to specialised microscopes, we have long been able to see the beauty of single atoms. But strange though it might seem, imaging larger molecules at the same level of detail has not been possible â" atoms are robust enough to withstand existing tools, but the structures of molecules are not. Now researchers at IBM have come up with a way to do it.

    emphasis mine.

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    .
  6. 5 linked rings by russotto · · Score: 4, Funny

    4 calling birds
    3 french hens
    2 turtle doves
    and a partridge in a pair tree?

    1. Re:5 linked rings by Shrike82 · · Score: 5, Funny

      You should have gone with:

      5 linked rings
      4 carbon bonds
      3 electrons
      2 tiny dots
      and a grainy image on my PC...

      --
      You can advertise in this sig from as little as £99.99 a month!
  7. Impressive by ballpoint · · Score: 5, Insightful

    This is a very impressive image that's in the same league as the famous Hubble deep field image. Both images confirm what was already known, but in a more direct and visual way.

    --
    Flourescent (adj): smelling like ground wheat.
  8. link to journal abstract by jschen · · Score: 5, Informative

    For anyone who wants the original paper, published in Science today, it may be found here. The abstract is free.

  9. The photo is of the electric field. by Futurepower(R) · · Score: 5, Informative

    Atoms are mostly empty space. The photo is of the electric field caused by the electrons.

    This photo is better. The article says it is a 20-hour time exposure. The photo was available through a Reddit story yesterday.

  10. I'm inpressed by the chemists who deduced ... by Anonymous Coward · · Score: 5, Insightful

    the structures of the molecule with such accuracy - without actually seeing it!

    Now, that's genius!

    1. Re:I'm inpressed by the chemists who deduced ... by MadTinfoilHatter · · Score: 4, Informative

      The funny thing is that the first person to deduce this (Friedrich August Kekulé von Stradonitz) realized the solution to the problem of structure, after having a dream in which a snake bit its own tail.

  11. Re:What the hell... by Jack+Malmostoso · · Score: 4, Informative

    The marking in Hz is most probably referred to the vibration of the cantilever (see how an AFM works), while the other unit is not Amps but Angstrom (1Å = 0.1nm). The pentacene molecule is long roughly 17Å. This stuff is on another planet of cool.

  12. Simply Awesome by gpronger · · Score: 5, Interesting

    I likely would have had this post up about 20 earlier, but I've just managed to pick myself off the floor after taking a look at the photo. As a chemist, I personally find the verification of theory a significant milestone in our understanding. It's one thing to have a theory, and then through somewhat serendipitous means, verify the theory, but to have an actual photo, brings it to a new level.

    Greg

    Yes, I do have a life outside the lab, but maybe not as much of one as I once thought.