Issues in GND computation for plagioclase

[Maël Allard]

Hi MTex community,

I'm currently dealing with an issue while trying to compute GND in plagioclase.
The problem occurs when defining slip systems, from TEM observations it is observed that the dislocation line

of [100](001) is in (001) between [1-10] and [2-10] axes (Montardi and Mainprice, 1987). The problem is these axes are respectively

at 57.29° and 38.15° from the Burger vector [100], and the code returns the following error (example for the first one):





% Define Burgers and dislocation lines


B_100 = Miller(1,0,0,CS,'uvw');

L_1m10 = Miller(1,-1,0,CS,'uvw');


% Set the energies of dislocations


E_edge_100 = (norm(ebsd.CS.aAxis))^2;

% Create dislocation systems


dS_001_100a = dislocationSystem(B_100, L_1m10,E_edge_100)




>>
Error using dislocationSystem
line vector and burgers vector should be either be orthogonal! or identical

So it seems that it is forced to be higher to certain angle in "dislocationSystem", because it works for angles of 64°,

but for triclinic symmetries may it be allowed to have lines at lower angles ?

There is also another point which is not clear for me, that when defining a screw dislocation system no glide plane

can be specify but some are observed on different planes (i.e. for different slip systems). Is this none specification normal

or is it a limitation of the method ?

Thank you,

Maël Allard