International
Tables for
Crystallography
Volume H
Powder diffraction
Edited by C. J. Gilmore, J. A. Kaduk and H. Schenk

International Tables for Crystallography (2018). Vol. H, ch. 3.8, p. 335

Section 3.8.6.1.1. Aspirin data with amorphous samples included

C. J. Gilmore,a G. Barra and W. Donga*

aDepartment of Chemistry, University of Glasgow, University Avenue, Glasgow, G12 8QQ, UK
Correspondence e-mail:  chris@chem.gla.ac.uk

3.8.6.1.1. Aspirin data with amorphous samples included

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As a demonstration of the handling of data from amorphous samples, five patterns for amorphous samples were included in the aspirin data and the clustering calculation was repeated. The results are shown in Fig. 3.8.10[link]. Fig. 3.8.10[link](a) shows the dendrogram. It can be seen that the amorphous samples are positioned as isolated clusters on the right-hand end. They also appear as an isolated cluster in the MMDS plot and the parallel-coordinates plots, as shown in Figs. 3.8.10[link](b) and (c). It could be argued that these samples should be treated as a single, five-membered cluster rather than five individuals, but we have found that this confuses the clustering algorithms, and it is clearer to the user if the data from amorphous samples are presented as separate classes.

[Figure 3.8.10]

Figure 3.8.10 | top | pdf |

The aspirin data including data from five amorphous samples. (a) The resulting dendrogram and (b) the corresponding MMDS plot. (c) The parallel-coordinates plot.








































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