Fixed atom and PES

Questions
#1

In Q-CHEM,whether Frozen Atoms or Potential Energy Surfaces use at the same time is possible?

#2

I assume by “Potential Energy Surfaces”, you mean JOBTYPE = PES_SCAN (potential energy scan). In that case, this appears to be incompatible with fixed-atom constraints.

With JOBTYPE=PES_SCAN and

$scan
stre 1 2 1.0 2.0 0.5
FIXED
1 XYZ
$end

Q-Chem returns a sensible error message:
Invalid constraint for potential energy scan