Euhedral Filter
Only a subset of the reflection list is used in the calculations.
The following filter commands can be used to create the subset.
angdistmax
With this filter parameter the angular psi-distribution can be selected. With
a small value, only reflections are selected that are widely distributed in
psi (recommended!). The maximum value is 2.5 (no filter). The default
value = 0.6
intmin
The minimal intensity depends on the original scaling of the dataset.
200.0 is the default value.
nhklmin
It makes no sense to use reflections, which were measured only once. Therefore
the redundancy must at least be 2 (which is the default).
thetamin
Reflections at low theta can be influenced by extinction. We therefore suggest
a minimum theta of 12° for molybdenum radiation.
Entering the filter routine
The "filter" routine is entered by the command
filter. The filter parameters mentioned above
can be changed by the operator within the loop of the routine or by calling the
routine later again.
Leaving the filter routine
The routine "filter" can be run as often as necessary. It can also be
called again in later stages of the refinements in order to change the
size of the subfile.
The routine can be left with or without saving the subfile.
Example
Steregraphic projection of the x-rays passing through the crystal.
The projection is viewed along the z-axis of the cartesian system.
On the left side, the top hemisphere, in the middle, the bottom
hemisphere. In green, the incoming rays (forming 3 different scans).
In magenta the outgoing rays. The reciprocal axes are also drawn.
Go to command overview.
Go to EUHEDRAL introduction.