What does the term Kspace denote in LAMMPS. I was reading the syntax for stress/atom and on that page, this term is used in the formulation.
Can someone please explain me meaning of this term.
Thank you.


“kspace” is a shorthand to refer to the long-range solver packages (Ewald, PPPM, USER-EWALD) that perform calculations of electrostatics (and in some cases dispersion) forces without a cutoff.

In this case, if you want to do stress calculations on systems with long-range interactions included, you will need to make sure those contributions are specifically accounted for. However, they will greatly slow down the efficiency of the code, as a significant amount of work is required (the PPPM code, for instance, requires 6 FFT’s).