Solution

ID: past-exam-of-the-chemistry-course-of-the-year-3-of-the-natural-sciences-course-of-the-university-of-cambridge/2022/paper-4/58/a/i/solution

Reality of the electron density implies . Writing and pairing positive and negative indices gives
The sign in the cosine follows from the supplied negative-sign Fourier-synthesis convention. is the mean electron density in the fractional-coordinate normalization.

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