Update 11_nearly_free_electron_model.md - prior knowledge

src/11_nearly_free_electron_model.md

@@ -9,6 +9,15 @@ pi = np.pi
 # Tight binding and nearly free electrons
 _(based on chapters 15–16 of the book)_  
 
+!!! success "Expected prior knowledge"
+
+    Before the start of this lecture, you should be able to:
+
+    - Write down the dispersion and wavefunction of an electron traveling in free space (by solving the Schrödinger equation).
+    - Describe the concept and relevance of reciprocal space and the 1st Brillouin zone. 
+    - Describe how the periodicity of a band structure (=dispersion) is related to the periodicity of a lattice.
+    - Recall how the band structure depends on the number of atoms/degrees of freedom within a unit cell 
+    
 !!! summary "Learning goals"
 
     After this lecture you will be able to: