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Electron In conduction band at 0K

  1. Nov 17, 2012 #1
    Electrons in the conduction band of metal will be attracted by the nucleus of atom?
    I wonder why there can be electron in the conduction band of metal at 0K .At 0K , all electron should lose its energy as(3/2)kT=0.
    Thank you
  2. jcsd
  3. Nov 17, 2012 #2


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    No, at 0K all electrons are in their ground-state. This does not mean that they can't move.
    You can't use classical physics in this case, electrons at 0K are most definitly not classical.
  4. Nov 17, 2012 #3
    Usually, you cannot say anything about force of attraction b/w electron and nucleus from the energy diagram. Conduction electron does not mean they are free to go everywhere.

    At 0K, fermi function wont allow any electrons to be in conduction band.

    PS: Where do you find these outrageous ideas?
  5. Nov 17, 2012 #4
    What defines a metal is that it doesn't have a forbidden band between a full valence and an empty conduction band. The shape of its bands means that the Fermi level passes right through one band. So at whatever temperature, you have always mobile charge carriers available in a metal.

    Also, only deep orbital electrons are local to one atom. Valence, conduction or metallic electrons (or better, electronic states) are shared among all atoms, even without thermal energy, because of the tunnel effect.

    It's just like in any chemical bond, where electrons are shared - by tunnel effect on the part of the bond orbital where the energy is positive.
  6. Nov 17, 2012 #5
    You mean (3/2)kT is classical? then I have study modern physics only can understand :Why At 0K ,electrons in ground state still can orbit ?

    But at 0K the electron of metal can be in conduction band.
    I am sorry if I have asked stupid questions.

    Thanks for replying.
  7. Nov 17, 2012 #6
    Dont be sorry. You did not ask a stupid question. But people usually dont think this stuffs.

    (3/2)kT is energy due to three degrees of freedom of a particle. So, yeah it is classical.
    In modern view, (I'm not sure) this view is not used widely.
  8. Nov 17, 2012 #7
    What does"on the part of the bond orbital " mean?
    At 0K electron can orbit the nucleus because of tunnel effect?
    Want to make sure:Can I say any electrons in conduction band are free from attractive force of nucleus?
  9. Nov 18, 2012 #8
    You have to understand orbital hybridization and chemical bonding to understand that in detail. Simply put when a electron is in an energy level and there's little distance to the adjacent energy level, the electron can tunnel through the gap between those two energy levels and occupy the second energy state. But remember that, these two energy levels have same energy and are separated in space and NOT separated in energy as in energy diagram.
  10. Nov 18, 2012 #9
    "Two energy levels have same energy and are separated in space " refers to orbital hybridization .
    This is the answer for explaining why even without thermal energy ,electrons can still stay as conduction or metallic electrons?

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