English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Thermodynamics of Water Dimer Dissociation in the Primary Hydration Shell of the Iodide Ion with Temperature-Dependent Vibrational Predissociation Spectroscopy

MPS-Authors
/persons/resource/persons21611

Heine,  Nadja
Molecular Physics, Fritz Haber Institute, Max Planck Society;

/persons/resource/persons85129

Esser,  Tim
Molecular Physics, Fritz Haber Institute, Max Planck Society;

/persons/resource/persons130085

Knorke,  Harald
Molecular Physics, Fritz Haber Institute, Max Planck Society;

Locator
There are no locators available
Fulltext (public)
There are no public fulltexts available
Supplementary Material (public)
There is no public supplementary material available
Citation

Wolke, C. T., Menges, F. S., Toetsch, N., Gorlova, O., Fournier, J. A., Weddle, G. H., et al. (2015). Thermodynamics of Water Dimer Dissociation in the Primary Hydration Shell of the Iodide Ion with Temperature-Dependent Vibrational Predissociation Spectroscopy. The Journal of Physical Chemistry A, 119(10), 1859-1866. doi:10.1021/jp510250n.


Cite as: http://hdl.handle.net/11858/00-001M-0000-0026-C1E2-C
Abstract
The strong temperature dependence of the I·(H2O)2 vibrational predissociation spectrum is traced to the intracluster dissociation of the ion-bound water dimer into independent water monomers that remain tethered to the ion. The thermodynamics of this process is determined using van’t Hoff analysis of key features that quantify the relative populations of Hbonded and independent water molecules. The dissociation enthalpy of the isolated water dimer is thus observed to be reduced by roughly a factor of three upon attachment to the ion. The cause of this reduction is explored with electronic structure calculations of the potential energy profile for dissociation of the dimer, which suggest that both reduction of the intrinsic binding energy and vibrational zero-point effects act to weaken the intermolecular interaction between the water molecules in the first hydration shell. Additional insights are obtained by analyzing how classical trajectories of the I·(H2O)2 system sample the extended potential energy surface with increasing temperature.