MOPAC: can we run THERMO immediately after the geometry optimzation?
OK, in between I found it, it is the GEO_DAT keyword, for example, reading in previously converged PM7 geometry of methane:

 AUX LARGE CHARGE=0 SINGLET  GEO_DAT="metan_geomopt_pm7.arc" THERMO(298,298)  PM7