when I’m running my esh script, I’m reaching this warning message :
“Info: force field type = “opls”
Info: force field name = “opls/2012/opls-ua”
Info: force field location = “/field”
Info: build for LAMMPS script in “…/build”
Warning: field ‘pcff_iff_nuwan’ not found;
Info: adding pressure sampling
Info: creating EMC build script “build.emc”
Info: assuming mass fractions”
and because of my field is not founded, I need to change my field manually in my build.emc to finally execute my build.emc file to get params and data file to use on lammps.
Is it possible a way to define my field path when my running my esh file using: perl emc_setup.pl pu_spherulitic.esh to use pcff field ?
To get straight to the point: you are missing the path to your field. For some reason, fields are not at the location, that EMC Setup is expecting them. EMC Setup uses two ways:
It tries to use the environment variable EMC_ROOT, which should be set to where your EMC distribution is residing. In my case this is $HOME/emc/v9.4.4
If the former fails, it uses the location of emc_setup.pl – which normally would be $EMC_ROOT/scripts – from which the field directory should be at $EMC_ROOT/scripts/../field
The line stating where fields are located, i.e.
Info: force field location = “/field”
tells me, that neither of the two above assumptions are satisfied. You can also provide a search path, if you have moved the field directory, by
ITEM OPTIONS
field_location your/field/location
field pcff_iff_nuwan
field_increment warn
...
ITEM END
Note that setting of field_location has to precede field. EMC Setup descends into provided field directories to search for the name as given by field.
As an aside – since I see you are thinking of using IFF – you can also rack-and-stack force fields. In this case, you can indicate what specific force to apply in the definition of your groups with keyword field or f, e.g.
ITEM OPTIONS
field pcff, iff
ITEM END
ITEM GROUPS
name1:f=iff [your][group]
name2 CCO
ITEM END
Typically, you would apply IFF to an imported crystal structure though, e.g.
ITEM CLUSTERS
structure import, name="crystal.car", field=iff, etc.
ITEM END