Help Privacy Policy Disclaimer
  Advanced SearchBrowse




Journal Article

The Free OD at the Air/D2O Interface is Structurally and Dynamically Heterogeneous


Tong,  Yujin
Physical Chemistry, Fritz Haber Institute, Max Planck Society;


Campen,  R. Kramer
Physical Chemistry, Fritz Haber Institute, Max Planck Society;

External Resource
No external resources are shared
Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available

Tong, Y., Verde, A. V., & Campen, R. K. (2013). The Free OD at the Air/D2O Interface is Structurally and Dynamically Heterogeneous. The Journal of Physical Chemistry B, 117(39), 11753-11764. doi:10.1021/jp406577v.

Cite as: https://hdl.handle.net/11858/00-001M-0000-0014-56B6-2
Air/water interfaces are both ubiquitous in the environment and technology and a useful model for hydrophobic solvation more generally. Previous experimental and computational studies have highlighted that molecular level markers of such an extended hydrophobic surface are broken hydrogen bonds and, as a result, OH groups that are not hydrogen bond donors: free OH. Understanding both the time-averaged structure and structural dynamics of these free OH thus plays a critical role in developing a quantitative, molecular level understanding of hydrophobic solvation. Here we show, by combining polarization-dependent vibrational sum frequency (VSF) spectroscopy and molecular dynamics simulation, that the free OD of D2O at the air/D2O interface is structurally and dynamically heterogeneous: that longer lived free OD groups tend to point closer to the surface normal, have a narrower orientational distribution, and are closer to the vapor phase. Knowledge of this structural heterogeneity should help link existing descriptions of hydrophobic solvation that focus either on the termination of the bulk hydrogen bond network or local density fluctuations. In addition the results of this study clarify that schemes to increase signal-to-noise ratios in VSF measurements by delaying the visible pulse relative to the infrared should be used only with independent constraints on the system’s structural dynamics.