Strain Broadening Model (Quartic form)
The following items correspond to anisotropic strain broadening modelled using a quartic form in reciprocal space. This correspond to an interpretation of the strains as due to static fluctuations and correlations between metric parameters [see J. Rodríguez-Carvajal, M.T. Fernandez-Díaz and J.L. Martínez, J. Phys: Condensed Matter 3, 3215 (1991) ]. The notation used is that of P. Stephens [Peter W. Stephens, J. Appl. Cryst. 32, 281 (1999)].
A maximum of 15 parameters can be given. The input format is different for the different Laue classes.
Laue class: -1
S_400, S_040, S_004, S_220, S_202
S_022, S_211, S_121, S_112, S_301
S_301, S_130, S_103, S_013, S_031
Laue class: 1 2/m 1
S_400, S_040, S_004, S_220, S_202
S_022, S_121, S_301, S_103
Laue class: 1 1 2/m
S_400, S_040, S_004, S_220, S_202
S_022, S_112, S_310, S_130
Laue class: mmm
S_400, S_040, S_004, S_220, S_202, S_022
Laue classes: 4/m, 4/mmm
S_400, S_004, S_220, S_202
Laue classes: -3 R, -3m R
S_400, S_004, S_112, S_211
Laue classes: -3, -3m1, -31m, 6/m, 6/mmm
S_400, S_004, S_112
Laue classes: m3, m3m
S_400, S_220