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Applying Bohr's Hydrogen model to a He ion

  1. Nov 10, 2004 #1
    Hey ppl,

    I was wondering, with a singly ionised He atom, can we apply the Bohr model, eg E = 13.6eV/n^2, to find the energy of the excited states? How would i go about that?
  2. jcsd
  3. Nov 10, 2004 #2


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    Nglecting all relativistic effects,u could aplly the formula,but with the restriction that the minimum energy is [tex] 13.6*4=54.4 [/tex] eV.which comes from the fact that for Helium ions [tex] Z=2 [/tex].
  4. Nov 12, 2004 #3
    Beta Battle...

    [tex]1s^1[/tex] ground state:
    [tex]E_{1s^1}(Z,n) = \frac{(13.6ev)Z_n^2}{n^2}[/tex]

    [tex]E_{1s^1}(Z,n) = \frac{\alpha^2 M_e c^2 Z_n^2}{2qn^2} = \frac{M_e}{2q} \left( \frac{\alpha c Z_n}{n} \right)^2[/tex]

    [tex]E_{1s^1}(Z,n) = \frac{M_e}{2q} \left( \frac{\alpha c Z_n}{n} \right)^2[/tex]

    This equation seems to work for ALL beta [tex]1s^1[/tex] states.

    Last edited: Nov 12, 2004
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