Introduction
Software
Experiment
Data processing
Post-processing and results evaluation
Advanced discussions
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GrainSpotter is a software which looks for grains in a 2D diffraction image.
To run it, you need a file with the ending .ini. When you perform a simulation with PolyXSim, it should automatically create such a file. It usually looks like this:
spacegroup 136 ! spacegroup [space group nr] !dsrange 0 4.2 ! dsrange [min max], d-spacing range, multiple ranges can be specified tthrange 0 25 ! tthrange [min max], multiple ranges can be specified etarange 0 360 ! etarange [min max], multiple ranges can be specified domega 0.5 ! domega [stepsize] in omega, degrees omegarange -28 28 ! omegarange [min max] degrees, multiple ranges can be specified filespecs g_vectors.gve grains.log ! filespecs [gvecsfile grainsfile] cuts 5 0.6 0.8 ! cuts [min_measuments min_completeness min_uniqueness] eulerstep 6 ! eulerstep [stepsize] : angle step size in Euler space uncertainties 0.1 0.2 .5 ! uncertainties [sigma_tth sigma_eta sigma_omega] in degrees nsigmas 2 ! nsigmas [Nsig] : maximal deviation in sigmas !minfracg 0.2 ! stop search when minfracg (0..1) of the gvectors have been assigned to grains !Nhkls_in_indexing 15 ! Nhkls_in_indexing [Nfamilies] : use first Nfamilies in indexing random 10000 ! use randomly chosen orientation seeds #trials !positionfit ! fit the position of the grain
Explanations of the .ini file:
| spacegroup | enter the space group number |
| dsrange | … |
| cut_first number | grain is chosen if there are at least this amount of peaks per grain |
| cut_second number | grain is chosen if there are at least this fraction of the expected peaks present |
| cut_third number | put in any number |
