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Q.2 Answer all parts In this question we consider the scattering of light from crystal structures in real space. This introduces the concept of a reciprocal lattice vector. Please articulate your understanding of the background to the question where possible in each answer. (a) Explain the concept of a primitive unit cell in your own words. Describe what type of conventional crystal structure is represented by the primitive unit cell shown in figure 1. Briefly, describe how a unit cell of this structure of this type can be constructed from a conventional unit cell. Figure 1: A primitive unit cell for a crystalline structure. (b) Starting with an orthogonal set of primitive basis vectors for the real lattice a = ax, b = by, & c = cz describe how a primitive set of basis vectors for the corresponding reciprocal lattice is given by A = =" 8. B = ->, and C = =" 2). Using the primitive basis vectors explain how the reciprocal lattice of a body centred cubic real lattice has a face centred cubic structure in reciprocal space