International
Tables for Crystallography Volume B Reciprocal space Edited by U. Shmueli © International Union of Crystallography 2010 
International Tables for Crystallography (2010). Vol. B, ch. 2.3, p. 246
Figure 2.3.1.1 ^{a}Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907, USA,^{b}CABM & Rutgers University, 679 Hoes Lane, Piscataway, New Jersey 08854–5638, USA, and ^{c}Department of Biological Sciences, Columbia University, New York 10027, USA 

Figure 2.3.1.1
Effect of `sharpening' Patterson coefficients. (1) shows a mean distribution of values with resolution, . The normal decline of this curve is due to increasing destructive interference between different portions within diffuse atoms at larger Bragg angles. (2) shows the distribution of `sharpened' coefficients. (3) shows the theoretical distribution of produced by a pointatom structure. To represent such a structure with a Fourier series would require an infinite series in order to avoid large errors caused by truncation. 