Greninger chart

Fig. 8-3 Greninger chart for the solution of back-reflection Laue patterns, reproduced in the correct size for a specimen-to-film distance D of 3 cm.

Fig. 8-4 Use of the Greninger chart to plot the pole of a reflecting plane on a stereographic projection. Pole V in (b) is the pole of the plane causing diffraction spot 1 in (a).

In the absence of a Greninger chart, the pole corresponding to any observed Laue spot may be plotted by means of an easily constructed stereographic ruler. The construction of the ruler is based on the relations shown in Fig. 8-10. This drawing is a... 

Fig. 8-9 Use of the Greninger chart to plot the axis of a zone of planes on the stereographic projection. is the axis of zone A.

This chart is exactly analogous to the Greninger chart for solving back-reflection patterns and is used in precisely the same way. It consists of a grid... 

Plot these spots on a sheet of graph paper graduated in inches. By means of a Greninger chart, determine the orientation of the crystal, plot all poles of the form 100), 110), and 111), and give the coordinates of the (100) poles in terms of latitude and longitude measured from the center of the projection. 

Figure 8. Back-reflection pattern of a gold crystal drawn on tracing paper superimposed on a Greninger chart.

A graphical method of doing this was devised by Greninger [8.1] who developed a chart which, when placed on the film, gives directly the y and 6 coordinates corresponding to any diffraction spot. To plot such a chart, we note from Fig. 8-2 that... 

The interpretation of the photograph obtained after about 20 min, is carried out by making use of a chart developed by Greninger (Fig. 7), a standard projection of the crystal system (Fig. 5 for the cubic system), and a table of the angles between the different faces (Table 1 for the cubic system). 

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