ECP Master Pattern Simulations

Last Update: 1/25/2022

ECP Master Pattern Simulations

The master pattern simulation for the ECP modality proceeds generally along the same lines as for an EBSD pattern, but the computation is faster since only one single energy bin must be considered for the BSE1 electrons. To set up the program parameters, execute the following command:

EMECPmaster -t

This will create the BetheParameters.template file and the EMECPmaster.template file. The former is described in more detail in the EBSD master computation help page; for the latter, the following parameters are available in the namelist file:

 &ECPmastervars
! no. of pixels in the X and Y direction will be 2*npx+1
 npx = 500,
! smallest d-spacing to take into account [nm]
 dmin = 0.05,
! name of EMMCOpenCL output file to be used to copy the MC data from for this master pattern run;
! This can be used to perform multiple master pattern runs starting from the same MC data set without
! having to rerun the MC computation.  Leave this variable set to 'undefined' if not needed.
 copyfromenergyfile = 'undefined',
! name of the energy statistics file produced by EMMCOpenCL program; relative to EMdatapathname
! this file will also contain the output of the master program
 energyfile = 'undefined',
! set combinesites to .TRUE. if you want the program to add all atomic site contributions 
! together in the master pattern; this will make the output file smaller, especially for 
! crystal structures with lots of atoms in the asymmetric unit.
 combinesites = .FALSE.,
! set to 'On' if you want Slack or Email notification at the end of program run
 Notify = 'Off',
! number of threads to run the master pattern
 nthreads = 1
 /

The parameters have the same meaning as for the EBSD master pattern computation; there is no Restart option, since the computation is generally rather fast (although for large low symmetry unit cells, this may still take several hours). The output of the program will be written to the same file that contains the Monte Carlo data. To execute the program, simply type:

EMECPmaster filename.nml