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What is the box in particle in a box?

  1. Oct 30, 2012 #1
    Hi, I am trying to demonstrate the relation between quantization of energy and wavelengths in a confined box for high school chemistry students. I am following an approach found in Atkins' "Chemical Principles". Anyways, its quite understandable, but I get the feeling maybe the box isn't actually what I think it is. I've been thinking of the box as the energy level (shell). But is it actually the orbital? Or something else entirely? Thanks.
  2. jcsd
  3. Oct 31, 2012 #2
    Is this a bad question? I understand its just a model, but what is the box analogous to for say, an atom of hydrogen?
  4. Oct 31, 2012 #3


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    A one dimensional box is a potential V(x) which is infinite for e.g. x<0, zero for x>=0 and x<=L and again infinite for x>L.
    It is not an energy level. The energies and orbitals arise when you solve the Schroedinger equation for a particle moving in that potential.
  5. Oct 31, 2012 #4


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    The box is really just a box: a volume with walls which are impenetrable for the particle. Although this is a valid approximation for some real physical systems, it is primarily a Gedankenexperiment which is easy to calculate and illustrates the behaviour of quantum mechanical systems. Especially, it is a quite bad model for atoms because they have no sharp boundary like the box.
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