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Atoms Energy Emission, Absorption

  1. Apr 16, 2007 #1
    I was wondering about the process of atom excitement/ionization. If you have a atom that has 4 energy levels and a emitted photon from a laser that had the wave characteristics (F,L,E) as not the valance electron, but the sub shell below the valance electron (match the sub shell energy gap), can the system excite that electron in the sub shell before the valance electron? If so what are the implications of this? Is the time span so short ~10 ns that the valance electron does not drop to lowest energy state, or does the valance electron drop one level and the excited electron stays in the valance ring? I guess a third part could be that as that because the atom absorbs the EM photon energy and not just the electron with the one shell's matching characteristics the atom could dissipate some energy through vibrations, etc and excite an electron? Basically is there a set order that electrons have to be excited by in the shell/cloud system (outer to center)? Thanks
  2. jcsd
  3. Apr 16, 2007 #2
    I would say like this. The atom always tend to have ground state. That means that no gaps should be in the orbitals (8 valent electrons). So get the example of producing methane. First one of the 2s electrons (of CH2) is excited and goes to the 2pz orbital. But to stop the possible refuse of the electrons (4 electrons in 4 orbitals, 1 electron in 1 orbital), so it combines into thetraedical arrangment. But how it do that? The 2px,2py and 2pz orbitals are on higher orbital level than the 2s orbital. So they go back for 5.55 eV and release that energy (by releasing photon). So the electron of the 2s orbital excites and goes for 5.55 eV above and all orbitals are on very similar orbital energy level and bond with four hydrogen atoms (methane). I hope this helped you.
  4. Apr 17, 2007 #3
    Thanks for the information. I will look into these comments. I will assume that a ground state and spherical charge orientation can be adjusted in distribution at some what will. We can excite valance electrons, while also creating hallow atoms (Z charge in outer orbital). While assuming it is probable that we could excite inner electrons before outer by adjusting the frequency similar to the atom not absorbing the energy at all, but the inner electrons absorbing the outer electrons being transparent (However, I think the atom as a whole absorbs the photon so I am not sure on this. Although, hitting a particular wave/electron I believe in the 10 ns of interaction would not transfer energy out to the atom as a whole and the inner wave/electron interaction would stay local and excite the inner wave/electron and the outer electron would de-excite). So although the atom as a whole absorbs the photon the wave is still location specific and not everywhere thus making it possible to miss the outer charge. Thanks for the help
  5. Apr 17, 2007 #4
    But probably it will excite all electrons (from inner and outer shell) because the electrons are going faster than the photon, maybe it can miss some orbitals but usually it hits all of them (this is logical theory).
  6. Apr 18, 2007 #5
    Auger Emission

    Thanks, for the information. I have looking into Auger Emissions and think that this shows a lot of it.
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