CP2K PM6 result does not consistent with MOPAC PM6

[bharat]

Dear Experts,

I did the semiempirical calculation with PM6 for the small system of AgO. 
CP2K gives the Heat of formation of 134.9850424864 kcal/mol whereas MOPAC 
gives the 98.21606 kcal/mol. The experimental Heat of formation is about 
53.0 kcal/mol.

I do not know why CP2K can not reproduce the same result as MOPAC.

Can anybody help me to figure out, what wrong is going on in CP2K 
calculation.

My simple input is following.

Thank you in advance.

Sincerely,
Bharat Sharma

&FORCE_EVAL
  METHOD Quickstep
  &DFT
   CHARGE 0
   LSD T
    &QS
      METHOD PM6
      &SE
       ANALYTICAL_GRADIENTS F
      &END
    &END QS
    &SCF
      SCF_GUESS ATOMIC
    &END SCF
  &END DFT
  &SUBSYS
    &CELL
      ABC 20.0 20.0 20.0
      PERIODIC NONE
    &END CELL
    &COORD
 O                 -2.48815585    0.31201747    0.00696372
 Ag                -4.60495278    0.41447825    0.06239400
    &END COORD
  &END SUBSYS
&END FORCE_EVAL
&MOTION
  &GEO_OPT
   MAX_ITER 5000
  &END GEO_OPT
&END MOTION
&GLOBAL
  PROJECT AgO
  RUN_TYPE GEO_OPT
&END GLOBAL
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