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Discrete stages in the solvation and ionization of hydrogen chloride adsorbed on ice particles


Ionization and dissociation reactions play a fundamental role in aqueous chemistry. A basic and well-understood example is the reaction between hydrogen chloride (HCl) and water to form chloride ions (Cl-) and hydrated protons (H3O+ or H5O2+). This acid ionization process also occurs in small water clusters1,2,3,4 and on ice surfaces5,6,7,8,9,10,11,12,13,14,15,16,17, and recent attention has focused on the mechanism of this reaction in confined-water media and the extent of solvation needed for it to proceed1,2,3,4,9,15,16,17. In fact, the transformation of HCl adsorbed on ice surfaces from a predominantly molecular form to ionic species during heating from 50 to 140 K has been observed8,13,14. But the molecular details of this process remain poorly understood. Here we report infrared transmission spectroscopic signatures of distinct stages in the solvation and ionization of HCl adsorbed on ice nanoparticles kept at progressively higher temperatures. By using Monte Carlo and ab initio simulations to interpret the spectra, we are able to identify slightly stretched HCl molecules, strongly stretched molecules on the verge of ionization, contact ion pairs comprising H3O+ and Cl-, and an ionic surface phase rich in Zundel ions, H5O2+.

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Figure 1: FTIR difference spectra of HCl on ice particles at 50 K and 15% coverage.
Figure 2: FTIR difference spectra for DCl adsorbate on D2O ice at 30% cover.
Figure 3: Cluster models used in ab initio calculations.


  1. 1

    Packer, M. J. & Clary, D. C. Interaction of HCl with water clusters: (H2O)nHCl, n = 1-3. J. Phys. Chem. 99, 14323–14333 (1995)

    CAS  Article  Google Scholar 

  2. 2

    Re, S., Osamura, Y., Suzuki, Y. & Schaefer, H. F. Structures and stability of hydrated clusters of hydrogen chloride, HCl(H2O)n, n = 1-5. J. Chem. Phys. 109, 973–977 (1998)

    ADS  CAS  Article  Google Scholar 

  3. 3

    Bacelo, D. E., Binning, R. C. & Ishikawa, Y. Ab initio Monte Carlo simulated annealing study of HCl(H2O)n (n = 3,4) clusters. J. Phys. Chem. A 103, 4631–4640 (1999)

    CAS  Article  Google Scholar 

  4. 4

    Chaban, G. M., Gerber, R. B. & Janda, K. C. Transition from hydrogen bonding to ionization in (HCl)n(NH3)n and (HCl)n(H2O)n clusters. J. Phys. Chem. A 105, 8323–8332 (2000)

    Article  Google Scholar 

  5. 5

    Hanson, D. R. & Ravishankara, A. R. Investigation of the reactive and non-reactive processes involving ClONO2 and HCl on water and nitric acid doped ice. J. Phys. Chem. 96, 2682–2691 (1992)

    CAS  Article  Google Scholar 

  6. 6

    Horn, A. B., Chesters, M. A., McCoustra, M. R. S. & Sodeau, J. R. Adsorption of stratospherically important molecules on thin D2O films using reflection absorption infrared spectroscopy. J. Chem. Soc. Faraday Trans. 88, 1077–1078 (1992)

    CAS  Article  Google Scholar 

  7. 7

    Chu, L. T., Leu, M. T. & Keyser, L. F. Uptake of HCl in water ice and nitric acid ice films. J. Phys. Chem. 97, 7779–7785 (1993)

    CAS  Article  Google Scholar 

  8. 8

    Delzeit, L., Rowland, B. & Devlin, J. P. Infrared-spectra of HCl complexed/ionized in amorphous hydrates and at ice surfaces in the 15-90 K range. J. Phys. Chem. 97, 10312–10318 (1993)

    CAS  Article  Google Scholar 

  9. 9

    Robertson, S. H. & Clary, D. C. Solvation of hydrogen halides on the surface of ice. Faraday Discuss. 100, 309–320 (1995)

    ADS  CAS  Article  Google Scholar 

  10. 10

    Banham, S. F., Horn, A. B., Koch, T. G. & Sodeau, J. R. Ionisation and solvation of stratospherically relevant molecules on ice films. Faraday Discuss. 100, 321–332 (1995)

    ADS  CAS  Article  Google Scholar 

  11. 11

    Graham, J. D. & Roberts, J. T. Interaction of HCl with crystalline and amorphous ice—implications for the mechanisms of ice-catalyzed reactions. Geophys. Res. Lett. 22, 251–254 (1995)

    ADS  CAS  Article  Google Scholar 

  12. 12

    Gertner, B. J. & Hynes, J. T. Model molecular dynamics simulation of hydrochloric acid ionization at the surface of stratospheric ice. Faraday Discuss. 110, 301–322 (1998)

    ADS  CAS  Article  Google Scholar 

  13. 13

    Isakson, M. J. & Sitz, G. O. Adsorption and desorption of HCl on ice. J. Phys. Chem. A 103, 2044–2049 (1999)

    CAS  Article  Google Scholar 

  14. 14

    Kang, H., Shin, T. H., Park, S. C., Kim, I. K. & Han, S. J. Acidity of hydrogen chloride on ice. J. Am. Chem. Soc. 122, 9842–9843 (2000)

    CAS  Article  Google Scholar 

  15. 15

    Allouche, A., Couturier-Tamburelli, I. & Chiavassa, T. Ab initio model study of the mechanism of hydrogen chloride ionization on ice. J. Phys. Chem. B 104, 1497–1506 (2000)

    CAS  Article  Google Scholar 

  16. 16

    Svanberg, M., Pettersson, J. B. C. & Bolton, K. J. Coupled QM/MM molecular dynamics simulations of HCl interacting with ice surfaces and water clusters—Evidence of rapid ionization. J. Phys. Chem. A 104, 5787–5798 (2000)

    CAS  Article  Google Scholar 

  17. 17

    Mantz, Y. A. et al. The interaction of HCl with the (0001) face of hexagonal ice studied theoretically via Car-Parrinello molecular dynamics. Chem. Phys. Lett. 348, 285–292 (2001)

    ADS  CAS  Article  Google Scholar 

  18. 18

    Devlin, J. P. & Buch, V. Surface of ice as viewed from combined spectroscopic and computer modeling studies. J. Phys. Chem. 99, 16534–16548 (1995)

    CAS  Article  Google Scholar 

  19. 19

    Zundel, G. Hydrogen bonds with large proton polarizability and proton transfer processes in electrochemistry and biology. Adv. Chem. Phys. 111, 1–217 (2000)

    CAS  Google Scholar 

  20. 20

    Jorgensen, W. L., Chandrasekhar, J., Madura, J. D., Impey, R. W. & Klein, M. L. Comparison of simple potential functions for simulating liquid water. J. Chem. Phys. 79, 926–935 (1983)

    ADS  CAS  Article  Google Scholar 

  21. 21

    Votava, C., Ahlrichs, R. & Geiger, A. The HCl-HCl interaction: From quantum mechanical calculations to properties of the liquid. J. Chem. Phys. 78, 6841–6848 (1983)

    ADS  CAS  Article  Google Scholar 

  22. 22

    Uras, N., Buch, V. & Devlin, J. P. Hydrogen bond surface chemistry: interaction of NH3 with an ice particle. J. Phys. Chem. B 104, 9203–9209 (2000)

    CAS  Article  Google Scholar 

  23. 23

    Devlin, J. P., Joyce, C. & Buch, V. Infrared spectra and structures of large water clusters. J. Phys. Chem. A 104, 1974–1977 (2000)

    CAS  Article  Google Scholar 

  24. 24

    Agmon, N. The Grotthus mechanism. Chem. Phys. Lett. 244, 456–462 (1995)

    ADS  CAS  Article  Google Scholar 

  25. 25

    Ando, K. & Hynes, J. T. Molecular mechanism of HCl acid ionization in water. J. Phys. Chem. B 101, 10464–10478 (1997)

    CAS  Article  Google Scholar 

  26. 26

    Lundgren, J. O. & Olovsson, I. The crystal structure of hydrogen chloride dihydrate. Acta Crystallogr. 23, 966–971 (1967)

    CAS  Article  Google Scholar 

  27. 27

    Dunning, T. H. Gaussian basis sets for use in correlated molecular calculations. J. Chem. Phys. 90, 1007–1023 (1989)

    ADS  CAS  Article  Google Scholar 

  28. 28

    Frisch, M. J. et al. Gaussian 98 (Gaussian, Pittsburgh, 1998)

    Google Scholar 

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Correspondence to V. Buch.

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Devlin, J., Uras, N., Sadlej, J. et al. Discrete stages in the solvation and ionization of hydrogen chloride adsorbed on ice particles. Nature 417, 269–271 (2002).

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