Hi,
in question 1c in the 2018 final exam the basis was computed as follows:
From there it is then concluded that the structure factor is computed as a function of delta as follows:
and I’m not really sure how this was done? The PLV’s for \delta = 0 and \delta ≠ 0 look completely different to me so I don’t understand how the basis was chosen for \delta ≠ 0 to compute that structure factor
Hi Karel, maybe my derivation helps.
I also got structure factors different from the answer model for question 1d. Are the answers incorrect or did I miss something?
For S(1 1 0) I forgot to multiply by l=0, so I see why that one becomes 0.
But for S(0 0 1) I still think the 3 should become a -1, due to h+l=k+l = 1 so you get (-1)^1 = -1
This gives
S(0 0 1) = f(-1+exp(2iπ∆/a)
This is true. It was already posted a bit earlier.
