a Repetition of solid state physics 2) Assume silicon crystal, i.e., fcc-Si (a 5.4 A) 2a) Write down the primitive lattice vectors. 2b) How many atoms No and electrons Ne does the primitive cell contain. 2c) How many atoms Na and electrons Ne does the conventional cell contain 2d) What are the concentrations of the atoms resp. the electrons. Answer it units of number of particles per cm?.