The physicists in my college and I have been struggling with a couple of questions on the revision problem set.
Firstly, in question 6.6, how would you prove that the reciprocal of an FCC orthorhombic lattice is a BCC orthorhombic lattice?
It was possible to take linear combinations of the PLVs to prove this for the cubic lattice but for the orthorhombic lattice the lattice constants are different sizes so this isn't possible.
We also struggled with problem 6.13, Mean Field Theory, and I see that another student has asked about this as well. I don't suppose it would be possible to talk through this problem in one of the revision lectures?