ABSTRACT
I. Introduction ...................................................................................................................... 175
A. Hydrogen-Bond Symmetrization ............................................................................. 175
B. Candidate Compounds and Promising Probe .......................................................... 176
II. Hydrogen-Bond Symmetrization in Ice........................................................................... 177
A. Crystal Structure ...................................................................................................... 177
B. Infrared Absorption Study ....................................................................................... 178
1. Symmetrization in Ice VIII ............................................................................... 179
2. Symmetrization in Ice VII ................................................................................ 181
3. Phase Diagram and Isotope Effect .................................................................... 182
III. Hydrogen-Bond Symmetrization in Hydrogen Chloride ................................................ 183
A. Crystal Structure ...................................................................................................... 183
B. Raman Scattering Study........................................................................................... 185
1. Symmetrization in HCl ..................................................................................... 185
2. Symmetrization in DCl ..................................................................................... 187
3. Isotope Effect on Stretching Vibration and Symmetrization ........................... 189
IV. Summary .......................................................................................................................... 190
References..................................................................................................................................... 191
The hydrogen bond is an intermolecular force connecting adjacent molecules rather tightly, often
producing the specific structure and property of hydrogen-bonded molecular solids. In contrast
to the isotropic nature of coulomb and van der Waals interactions, the hydrogen bond has a strong
directional feature and hence plays a dominant role in molecular arrangement. The hydrogen atom
loses its electron to another atom in an adjacent molecule and the bare proton strongly attracts the
proton-sharing neighboring molecules. In addition, the proton can move along the hydrogen-
bonding axis by thermal activation or tunneling motion, allowing a variety of phase transitions with
proton ordering or disordering. These characteristics of the hydrogen bond are responsible for the
helical conformation of DNA and the dielectric property of ice, etc.
