Some components require external data files, e.g. lattice crystallographic definitions for Laue and powder pattern diffraction, \(S(q,\omega )\) tables for inelastic scattering, or transmission/reflectivity curves. Such files distributed with McStas are located in the data sub-directory of the library and are accessible to any component using the read_table-lib shared library (see section B.2) without needing local copies.
| MCSTAS/data | Description |
| *.lau | Laue pattern file, as issued from Crystallographica. For use with Single_crystal, PowderN, and Isotropic_Sqw. Data: [ h k l Mult. d-space 2Theta F-squared ] |
| *.laz | Powder pattern file, as obtained from Lazy/ICSD. For use with PowderN, Isotropic_Sqw and possibly Single_crystal. |
| *.trm | transmission file, typically for monochromator crystals and filters. Data: [ k (Angs-1) , Transmission (0-1) ] |
| *.rfl | reflectivity file, typically for mirrors and monochromator crystals. Data: [ k (Angs-1) , Reflectivity (0-1) ] |
| *.sqw | \(S(q,\omega )\) files for Isotropic_Sqw component. Data: [q] [\(\omega \)] [\(S(q,\omega )\)] |
| Table 7.1.: | Data files of the McStas library. |