anchor.diff:    call thermo_data%init(hfile, n_buffer=50, step=N_MD_steps, time=N_MD_steps*dt)
   
     call PTkill(config)
  +
  +  do n_blocks = 1, 6
  +     if (block_length**n_blocks >= N_loop/block_length) exit
  +  end do
  +  call msd%init(block_length, n_blocks, dim=3)
   
     if (dimer) then
        colloids% species(1) = 1
  
positive.code:         call elem_vx% append(vx% data, i, i*tau)
          call elem_vx_count% append(vx% count, i, i*tau)
          call vx% reset()
       end if
  
       call varia%tic()
  
negative.code:               end if
             end do
          end if
  
          so_max = solvent% maximum_displacement()
          co_max = colloids% maximum_displacement()
  