After getting FT and DF maps

After getting FT map (Fourier Transform) I found that the peak of
nucleus is in opposite direction(entering inside). So I couldn't
understant it why. From coutours of it what can we conclude about
crystal structure informations? And the contours of Difference Fourier
what can we know the crystal sturcture informations? Thanks in advace.

sincerly yours,

ZAW

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