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Most Detailed Photos of an Atom Yet
BuzzSkyline writes "Ukrainian researchers have managed to take pictures of atoms that reveal structure of the electron clouds surrounding carbon nuclei in unprecedented detail. Although the images offer no surprises (they look much like the sketches of electron orbitals included in high school science texts), this is the first time that anyone has directly imaged atoms at this level, rather than inferring the structure of the orbitals from indirect measurements such as electron or X-ray interferometry."
looks like it was done in MS paint to me...
If you mod me down, I will become more powerful than you can imagine....
This is amazing. We'd theorised orbitals to exist, and they worked very well. We could calculate the shapes of molecules and make detailed predictions that came true to 10 decimal places. Quantum mechanics as applied to electrons in atoms is the most successful and the most rigorously tested theory ever developed.
And yet, to finally see a real orbital, not a simulation. Looks like a 1s and a 2p, right there for the looking!
I am one of many. My idea is not unique, nor do I expect my voice alone to sway you. I speak in a chorus of opinion.
"Leo Gross and his colleagues at IBM in Zurich, Switzerland, modified the AFM technique to make the most detailed image yet of pentacene, an organic molecule consisting of five benzene rings"
http://www.newscientist.com/article/dn17699-microscopes-zoom-in-on-molecules-at-last.html
wot no sig
The ability to directly measure electron density is quite an old technique. STMs and AFMs have been doing this since the very beginning.. I agree with the researcher's quote in the article that it's good to develop a complementary technique(FEEM) abd at best that's its contribution. I'd be happy to hear what else it contributes. though I don't quite agree with his or the editors spelling! ;) "it's always good to have complimentary approaches,"
The unscaled photo is here:
http://insidescience.org/polopoly_fs/1.918!image/671260397.jpg
There are other ones like this one or even the inside of one like here
Don't fight for your country, if your country does not fight for you.
On my monitor, the unzoomed images are about 3cm across. This corresponds to a magnification factor of around 100 million! Awesome!
pi = 2*|arg(God)|
Why? Because the "orbitals" are actually solutions of the Schroedinger Wave Equation. They are images or a probability distribution in abstract space. Electrons are not clouds or points, they are things we don't really understand but describe by means of quantum mechanics. So I am deeply suspicious of the picture, because there is no physical object of that shape to image.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
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(not actual size)
Here's a picture of a dupe, complete with comments.
It's not a dupe -- that was a different story, as you would know if you had compared TFA from each story.
Pirate Party UK
So this is what's powering my netbook!
ignore. Reply done to undo bad moderation
C. Sagan : A demon haunted world:
http://www.amazon.com/gp/product/0345409469/
visit randi.org
They do look like the classical orbitals, don't they?
However, there are some problems with interpreting the image as a photograph of an orbital. What the FEEM does is to charge up a very sharp point. The actual voltage may not be very big, but the local field strength depends on screening and curvature, so you can get very large electrostatic fields around sharp features, and if you get the balance right, electrons will leave the sharp points, zoom down the field lines, and get imaged. I remember seeing a sharp tungsten needle in a FEEM back in the seventies, and seeing the individual atoms. This sort of thing provided the first real evidence of a screw dislocation. You got a strange projection of the tip of the needle, as the electrostatic field tended to map the roughly spherical tip onto a flat plane.
So what is happening here? Our field stripping an electron from the orbital. We are getting a map of the electron flows as focused by the electrostatic field. We calculate the trajectory back through the electrostatic field and guess some sort of map of emission. They must have stripped hundreds or thousands of orbital electrons from the same atom, and replaced them to get each image. However, if an orbital 'pokes out' of the atom, or forms a 'sharp feature' (inverted commas because they are wave functions, so these concepts are a bit hard to define) then we get a bright spot. The really cool bit is getting the atom to go back to the same hybridization state hundreds of times, so we got the two-lobed picture.
It's dead clever. However, for my money, the atomic force probes are cooler as they can measure the fields without stripping the electrons. But, as the reviewer said, it takes all sorts...
Electrons act like both particles and waves, following the laws of quantum mechanics. They are not really like moons traveling around planets in a neat circle.
I'm not a physicist but my understanding is that each element has a different number of electrons balancing the positive charge of the protons in the nucleus. These electrons form electron shells which are at different energy levels, and the shells are composed of a combination of atomic orbitals.
Quantum physics says that one cannot know where an electron is until you measure it. The three-dimensional geometric shape of an orbital indicates where the probability is highest that the electron will be found, but it could be just about anywhere. Some orbitals are spherical but others are very different shapes.
Here are some wikipedia links:
Atomic Orbitals
Electron Configuration
Electron Shells
... you can see Bigfoot in the background!
Atoms are blue. I guess that explains why the sky is blue...it's full of atoms.
Orbitals are not real ! They are mathematical constructs and they are not observables. People think that just because you can calculate something it is real, that is not the case.
That a derived quantity is "just" a calculated approximate model of some part of the universe doesn't mean it isn't real. Forget about orbitals and quantum mechanics, consider planetary orbits and classical mechanics. There is no such thing as a closed elliptical orbit as depicted in the textbooks. All orbits are unclosed.
Physics IS building models. Models are real even if they are incomplete:
http://www.revell.com/catalog/products/buzz_aldrin_rocket_hero.html
It may not be Buzz, but it shares the quality of physical existence with him. (And Buzz is himself not the man he was on the Moon.) The absurdity of Moon-landing deniers lies in the fact that each and every one of us spends our entire life embedded in outer space. Where else would be be? The evolving Earth is far more special a place than just another desiccated Moon.
Thanks for responding. This could do with some mod points but I can't mod and post...so I'll respond. It's interesting to think about what is happening here. It's possibly unhelpful to refer in the same sentence to "current" and "electrons" but I know what you mean, though I would rephrase it a little to help my own understanding. The "current" did not cause the carbon atom to give off electrons; rather, the potential difference enabled some electrons to pass along the carbon chain until they left the tip, and the path of the emerging electrons was probabilitistically interfered with in a way that reflected the solution of the Schroedinger wave equation for the outer electrons of the end atom. That's a very interesting experiment. The benefit of using carbon atoms in a molecule is that the bond angle presumably locks the orientation of the P orbitals sufficiently to enable the experiment. So for many atoms it simply wouldn't work, and what we are seeing here is not an image per se but something more like the result of the Rutherford/Geiger/Marsden experiment. It looks like a significant experiment, but the summary is quite wrong as to what is being shown.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."