5 ms·

Actual pictures of electron densities (orbitals)

43 points by rms 17y ago

stuntgoat 17y ago
I read that electrons inside us are moving around 4.9 million miles per hour.
- dhimes 17y ago
  You are a little off-topic here, but you may no know it. The number you are referring to is (I think, but your number is a little high...) for the average (specifically, the r.m.s speed) of an electron which is one of many (classical) things all at the same temperature (that is,in thermal equilibrium), at the temperature of the human body. If you're not familiar with these concepts, re-read the above but skip the stuff in parentheses.
  - stuntgoat 17y ago
    Thank you for letting me know I am a bit off topic. I had just read this: http://education.jlab.org/qa/electron_01.html http://education.jlab.org/qa/electron_01.html and converted to MPH. I was contributing something I thought was of interest and very much on topic.
    - dhimes 17y ago
      You might like this one better: http://wiki.answers.com/Q/How_fast_do_electrons_move_between_orbitals http://wiki.answers.com/Q/How_fast_do_electrons_move_between...
nopassrecover 17y ago
I've seen this same picture with different articles 3 times in the last month at least on HN.
m0th87 17y ago
I don't get how this stuff works. My understanding is that it was impossible to "see" electrons because they're so small that photons can't bounce off of them. How does this work? Also, how do they color it? Is it artificially added? I can't see why it would be naturally blue.
- jonmc12 17y ago
  http://en.wikipedia.org/wiki/Field_emission_microscopy http://en.wikipedia.org/wiki/Field_emission_microscopy
- lucifer 17y ago
  Where is the electron in that picture? It is "the electron density around one nucleus".
  - grinich 17y ago
    Finding the electron is tricky business. That question goes deep into quantum mechanics. http://en.wikipedia.org/wiki/Uncertainty_principle http://en.wikipedia.org/wiki/Uncertainty_principle
- JabavuAdams 17y ago
  This doesn't answer your question, but photons definitely can interact with (bounce off) electrons. All optical properties we see macroscopically (light interacting with objects) can be broken down to photons interacting with electrons. The Quantum Electro-Dynamics theory (QED) explains this. There are actually some really great and entertaining free video lectures about this, given by Richard Feynman: http://vega.org.uk/video/programme/45 http://vega.org.uk/video/programme/45 Now, I think what you were referring to is that we can't see electrons in an optical microscope because the electrons are smaller than the diffraction limit imposed by visible lights wavelengths. So, in my admittedly limited understanding, you can't see an electron with a light microscope, but almost everything we consider optics is determined by electron-photon interactions.

43 points by rms 17y ago

stuntgoat 17y ago

I read that electrons inside us are moving around 4.9 million miles per hour.

dhimes 17y ago
You are a little off-topic here, but you may no know it. The number you are referring to is (I think, but your number is a little high...) for the average (specifically, the r.m.s speed) of an electron which is one of many (classical) things all at the same temperature (that is,in thermal equilibrium), at the temperature of the human body. If you're not familiar with these concepts, re-read the above but skip the stuff in parentheses.
- stuntgoat 17y ago
  Thank you for letting me know I am a bit off topic. I had just read this: http://education.jlab.org/qa/electron_01.html http://education.jlab.org/qa/electron_01.html and converted to MPH. I was contributing something I thought was of interest and very much on topic.
  - dhimes 17y ago
    You might like this one better: http://wiki.answers.com/Q/How_fast_do_electrons_move_between_orbitals http://wiki.answers.com/Q/How_fast_do_electrons_move_between...

nopassrecover 17y ago

I've seen this same picture with different articles 3 times in the last month at least on HN.

m0th87 17y ago

I don't get how this stuff works. My understanding is that it was impossible to "see" electrons because they're so small that photons can't bounce off of them. How does this work? Also, how do they color it? Is it artificially added? I can't see why it would be naturally blue.

jonmc12 17y ago
http://en.wikipedia.org/wiki/Field_emission_microscopy http://en.wikipedia.org/wiki/Field_emission_microscopy
lucifer 17y ago
Where is the electron in that picture? It is "the electron density around one nucleus".
- grinich 17y ago
  Finding the electron is tricky business. That question goes deep into quantum mechanics. http://en.wikipedia.org/wiki/Uncertainty_principle http://en.wikipedia.org/wiki/Uncertainty_principle
JabavuAdams 17y ago
This doesn't answer your question, but photons definitely can interact with (bounce off) electrons. All optical properties we see macroscopically (light interacting with objects) can be broken down to photons interacting with electrons. The Quantum Electro-Dynamics theory (QED) explains this. There are actually some really great and entertaining free video lectures about this, given by Richard Feynman: http://vega.org.uk/video/programme/45 http://vega.org.uk/video/programme/45 Now, I think what you were referring to is that we can't see electrons in an optical microscope because the electrons are smaller than the diffraction limit imposed by visible lights wavelengths. So, in my admittedly limited understanding, you can't see an electron with a light microscope, but almost everything we consider optics is determined by electron-photon interactions.