electron transfer coupling calculation failure

[Maryam Ghotbi]

Hi! I have been trying to calculate the Electron Transfer Coupling Energy |V(RP)| between dimer molecules M1 and M2 which together have the total geometry section "tot" , but I have convergence issues and I hope you could help me. This input does not give me a particular error but gets stuck where it is trying to calculate the ET reactants and generate  HeB.movecs and the run times out after 4 days or something. I have tried various threshold values but it always get stuck near convergence criteria but never meets it. 

I hope you all can take a look. Thanks!

basis "ao basis"  
* library  6-311G(d,p)
END

geometry M1
   C       -6.49964       -3.35670       -1.70116
   C       -5.57818       -2.46157       -0.89601
   C       -6.44677       -0.23953       -1.56301
   C       -4.39610        2.78367       -0.64775
.

.

.
   F       -9.07268       -2.57504        1.40387
   F       -9.15667       -0.48817        2.40195
   B       -8.63005       -1.26567        1.39057
end

charge -1
set geometry M1

scf
 uhf
 direct
 nopen 1
 doublet
 maxiter 500
  sym off
 adapt off

 vectors output M1don.movecs

 
end
task scf
charge 0

scf
 uhf
 direct
 nopen 0
 singlet
 maxiter 500
   sym off
 adapt off
 vectors output M1acc.movecs
end

task scf


geometry M2
   C        2.72166       -2.93282        0.79112
   C        3.74082       -2.05107        1.49030
   C        3.94273       -0.24016       -0.18261
.

.

.
   F        0.34457        2.09047        2.32127
   B        0.86929        0.87484        1.90400
end

scf
 uhf
 direct
 nopen 0
 singlet
 vectors output M2acc.movecs
 maxiter 500
   sym off
 adapt off
end

task scf

charge -1

scf
 uhf
 direct
 nopen 1
 doublet
 vectors output M2don.movecs
 maxiter 500
 sym off
 adapt off
end

task scf
geometry tot noautosym noautoz
   C       -6.49964       -3.35670       -1.70116
   C       -5.57818       -2.46157       -0.89601
   C       -6.44677       -0.23953       -1.56301
.

.

.
   F        0.01474       -0.19449        2.16243
   F        0.34457        2.09047        2.32127
   B        0.86929        0.87484        1.90400
end
set geometry tot
charge -1


#ET reactants:
scf
    uhf;maxiter 3000; adapt off; sym off; vectors input fragment M1don.movecs M2acc.movecs output HeB.movecs    
end

task scf

#ET products:
scf
  uhf;maxiter 3000; adapt off; sym off; vectors input fragment M1acc.movecs M2don.movecs output HeA.movecs  
end

task scf


et
 vectors reactants HeA.movecs
 vectors products HeB.movecs
end
task scf et