anchor.diff:             do k=1, colloids% Nmax 
                 if (colloids% pos(1,k) > bufferlength) then
                    on_track = .false.
  -                 write(*,*) on_track
  +                 write(*,*) 'on_track', on_track
                 end if 
              end do
           end if
  
positive.code:            do k=1, colloids% Nmax 
                if (colloids% pos(1,k) > solvent_cells% edges(1)) then
                   stopped = .true.
                   write(*,*) stopped
                end if 
             end do
          end if
  
negative.code: 
    n_threads = omp_get_max_threads()
    allocate(state(n_threads))
    call threefry_rng_init(state, PTread_c_int64(config, 'seed'))
  
    call h5open_f(error)
  
  