Is there a default setting for the force of an atom?

Normally in VASP, there are two options for converge: ediff and ediffg, but I’m using the
’ JOBTYPE OPT
METHOD B3LYP
BASIS 6-311++G(d,p)
SCF_CONVERGENCE 7
THRESH 12
MAX_SCF_CYCLES 9000
SYMMETRY FALSE
SYM_IGNORE TRUE

I optimized it with the above options.

What I’m wondering is, like ediffg, tilt, force, and other terms are set by default even if you don’t set them separately, and I’m very curious about those options.

There are stopping criteria based on forces (magnitude of gradient), step size (displacement), and energy change, with sensible defaults. See:
https://manual.q-chem.com/latest/topic_ts_Job-Control-Optimize.html