anchor.diff:    type(h5md_element_t) :: n_solvent_el, catalytic_change_el, bulk_change_el
   
     double precision :: colloid_pos(3,2)
  +  double precision :: com_pos(3)
     type(h5md_file_t) :: hfile
     type(h5md_element_t) :: dummy_element
     integer(HID_T) :: fields_group, params_group
  
positive.code:         end if
       end if
  
    end do setup
  
    call thermo_data%append(hfile, temperature, e1+e2+e_wall, kin_e, e1+e2+e_wall+kin_e, v_com, add=.false., force=.true.)
  
    write(*,*) 'n extra sorting', n_extra_sorting
  
    call solvent_io%position%append(solvent%pos)
    call solvent_io%velocity%append(solvent%vel)
  
negative.code:                  write(*,*) 'on_track', on_track
                end if
             end if
             if (.not. on_track) i_release = i
          end if
  
          if ((.not. on_track) .and. (buffer_length/=0))then
  