anchor.diff:  
     write(*,*) 'n extra sorting', n_extra_sorting
   
  +  call solvent_io%position%append(solvent%pos)
  +  call solvent_io%velocity%append(solvent%vel)
  +  call solvent_io%image%append(solvent%image)
  +  call solvent_io%species%append(solvent%species)
  +
     call dimer_io%close()
  +  call solvent_io%close()
     call hfile%close()
     call h5close_f(error)
   
  
positive.code:   dimer_io%id_info%store = .false.
    dimer_io%position_info%store = .true.
    dimer_io%position_info%mode = ior(H5MD_LINEAR,H5MD_STORE_TIME)
    dimer_io%position_info%step = N_loop
    dimer_io%position_info%time = N_loop*dt
    dimer_io%image_info%store = .true.
    dimer_io%image_info%mode = ior(H5MD_LINEAR,H5MD_STORE_TIME)
    dimer_io%image_info%step = N_loop
    dimer_io%image_info%time = N_loop*dt
    dimer_io%velocity_info%store = .true.
    dimer_io%velocity_info%mode = ior(H5MD_LINEAR,H5MD_STORE_TIME)
    dimer_io%velocity_info%step = N_loop
    dimer_io%velocity_info%time = N_loop*dt
    dimer_io%species_info%store = .true.
    dimer_io%species_info%mode = ior(H5MD_LINEAR,H5MD_STORE_TIME)
    call dimer_io%init(hfile, 'dimer', colloids)
  
    call random_number(solvent% vel(:, :))
    solvent% vel = (solvent% vel - 0.5d0)*sqrt(12*T)
  
negative.code:   type(thermo_t) :: thermo_data
    double precision :: temperature, kin_e
    type(particle_system_io_t) :: dimer_io
    type(particle_system_io_t) :: solvent_io
  
    call PTparse(config,get_input_filename(),11)
  
  