Problem with massless atom

Dear Lammps Community,

I am trying to use massless atom with charge to create CO2-PHAST model. I used ‘fix rigid’ for this approach. I have checked the mailing list and it seems it should work, but it does not. I am getting the error message:

Dear Lammps Community,

I am trying to use massless atom with charge to create CO2-PHAST model. I used ‘fix rigid’ for this approach. I have checked the mailing list and it seems it should work, but it does not. I am getting the error message:

ERROR: Invalid mass value (…/atom.cpp:1177)

Could you please help me?

It works, if you use a very small mass. Or comment out the check. Due to the generality of many lammps modules masses equal to zero cannot be accepted, but a mass of, say, 1.0e-10 is indistinguishable from 0.0 for all practical purposes.

Axel

Dear Axel,

Thank you for your clear and helpful explanation!

Kind Regards,
Evgeniya