anchor.diff:              ! 1.1 Generate first random excitation and probability of spawning there from cdet 
               !    (in this case we stay on the same place)
               Pgen_ki = 1
  -            hmatel_ki =  sc0_ptr(cdet%f) - fold_line !***optimise this with stored/calculated values
  +            hmatel_ki =  sc0_ptr(cdet%f) - H00 - fold_line !***optimise this with stored/calculated values
               
   
               ! 1.2 Generate the second random excitation 
  
positive.code:             connection%nexcit = connection_ki%nexcit + connection_jk%nexcit
              ! (ii)  combine the annihilations
              connection%from_orb(:connection_ki%nexcit) = &
               connection_ki%from_orb(:connection_ki%nexcit)
              connection%from_orb(connection_ki%nexcit+1:connection%nexcit) = &
               connection_jk%from_orb(:connection_jk%nexcit)
  
              ! (iii) combine the creations
              connection%to_orb(:connection_ki%nexcit) = &
  
negative.code:             call create_excited_det_complete(cdet, connection_ki, cdet_excit) !could optimise this with create_excited det - we only need %f
              ! (ii) calculate Pgen and hmatel on this site       
              Pgen_jk = 1
              hmatel_jk =  sc0_ptr(cdet_excit%f) - H00 - fold_line !***optimise this with stored/calculated values
              
              ! 2. Probability of gening...
              pgen = P_o * Pgen_ki * Pgen_jk
  