1. The problem statement, all variables and given/known data In the tight binding model, (E=Eo + alpha + (2gamma coska)), how are parameters alpha and gamma affected if the lattice spacing, a, is increased? I know the equations for gamma and alpha but can't type them in here because they involve integrals and I don't know how to put those in on this forum. Thanks in advance! Sorry, didn't realise how the forums worked, so posted in this area instead. Its taking far too long to figure out how to post the equations in latex on here so i apologise but this isnt technically homework help. My final year solid state physics 2 exam is tomorrow and this wasn't in our notes but is in the revision questions handed out so please don't delete this one!