Helium - part 2 - The spin

2010.09.16 previous lecture note 2010.09.23 next lecture note

Helium - part 2 - The spin 21.09.2010

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Here we combine the spatial functions discussed in last lecture
with the spin functions

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When we have antisymmetric functions, the states (a,b) must be different
Also for spin, alpha, beta G.S. - Ground state ( for hydrogen 1s - here both in 1s)

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The observed energies are E₀ for the singlet and E₁ for the triplet.
Then an effective spin-spin interaction can be derived

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(we had some problems with this simple task!! Repeat it at home for yourself!)

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The above equation is missing in our EXAM notes

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2010.09.16 previous lecture note 2010.09.23 next lecture note