Importing Oxford Instruments - HKL *.ctf files for trigonal symmetry minerals e.g. calcite

[DavidMainprice]

Using MTEX 4.4.0 I imported a calcite data set. I started to do a few calculations on e-twins with the twin plane Miller(-1,0,1,8,ebsd('Calcite').CS,'hkil'), I could get correct misorientation for this twin.

Then I looked at the import wizard generated 'Specify Crystal and Specimen Symmetries' section

%% Specify Crystal and Specimen Symmetries

% crystal symmetry CS = {... 'notIndexed',... crystalSymmetry('-3m1', [4.99 4.99 17.064], 'X||a', 'Y||b*', 'Z||c', 'mineral', 'Calcite', 'color', 'light blue')};

% plotting convention setMTEXpref('xAxisDirection','east'); setMTEXpref('zAxisDirection','outOfPlane'); %% Specify File Names

% path to files pname = '/MatLab_Programs';

% which files to be imported fname = [pname '/CMHD_ad.ctf'];

%% Import the Data

% create an EBSD variable containing the data ebsd = loadEBSD(fname,CS,'interface','ctf',... 'convertSpatial2EulerReferenceFrame');

ALL Oxford Instruments - HKL ebsd files use the Euler angle convention 'X||a' and 'Z||c' but here we have 'X||a', 'Y||b', 'Z||c', 'mineral', 'Calcite', so the Euler frame rotated in this case 30 degrees about the c-axis which will make all MTEX analysis in error !!!

See diagram

all the best David

[DavidMainprice]

I have forgotten mention you can correct this by editing the line crystalSymmetry('-3m1', [4.99 4.99 17.064], 'X||a*','Z||c', 'mineral', 'Calcite', 'color', 'light blue')};

all the best David