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Radiation absorption by an atom

  1. Feb 10, 2013 #1
    When we shine light on an atom, it can absorbs this radiation, stimulating its electrons to jump to a more energetic energy level. This lasts too little time, and when the electrons come back to their original (fundamental) energy level, they emit the same energy they had absorbed before. This energy levels, though, are quantized. And by what I've understood, the atoms can only ABSORB and emit some discrete frequencies. So, I'm confused about the following:

    Consider the hydrogen atom.
    To pass from the n=1 to the n=2 energy level, we need a radiation of 13,6 (1/1² - 1/2²) = 10,2 eV.
    What would happen if we shine a monochromatic light of energy hf = 10,3 eV?
    Would the atom absorb that radiation?
     
  2. jcsd
  3. Feb 10, 2013 #2

    Bill_K

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    Light does not just excite atoms, it also scatters off them.
     
  4. Feb 10, 2013 #3
    What does it mean?
     
  5. Feb 10, 2013 #4

    Bill_K

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    Scattering is a billiard-ball collision in which some of the energy and momentum of the photon is transferred to the atom. You might take a look at this Wikipedia page.
     
  6. Feb 10, 2013 #5
    Thank you. I've read your page about the topic, can you tell me if I understood it right?

    By what I've understood, the excess of energy is absorbed by the atom, making it vibrate in different levels of vibration (rayleigh scattering). Is this right?
    Are this vibration levels quantized too? By what I know so far, vibration is a type of movement that does not change the mass center of a molecule. Could this excess of energy be added to the translational or rotational energies too?
     
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