Figure shows a plane view of the Brillouin zone of a square lattice, with some points of high symmetry labelled. Sketch the energies of the free-electron bands up to E~1Oh2/ma using the following simple k E relationship: [h2(q - 602] E: 2m where traverses the path P > M > X > F along the straight lines shown. You will need to consider dispersion curves originating from several neighboring Brillouin zones. II/a Figure: a plane View of the Brillouin zone of a square lattice with some points of high symmetry labelled