Raman Intensities of HDO and Structure in Liquid Water

Abstract

Photoelectric Raman spectra of HDO in 5-mole % isotopically substituted water show single, broad, slightly asymmetric bands in both of the regions containing the uncoupled fundamental stretching motions. An empirical correlation between O–H or O—D stretching frequency and O···O hydrogen-bonded distance has been used to map the frequency coordinate of the spectra onto an intermolecular distance scale, and the Raman bands are replotted on this abscissa. The resulting intermolecular distribution functions for liquid water agree with x-ray results and support the suggestion that the breadth of the HDO uncoupled stretching bands reflects the variation of intermolecular distance. Moreover, it is noted that the corresponding infrared and Raman bands are almost superposable, and that this indicates little hydrogen-bond breakage in liquid water. The distribution of intermolecular distances represented by the spectra is compared to that incorporated in some of the structural models for liquid water. It appears that a successful model should incorporate the homogeneity, isotropy, coherence, and disorder of the liquid in its local structure.

Pre‐processing in biochemometrics: correction for path‐length and temperature effects of water in FTIR bio‐spectroscopy by EMSC

“…This interpretation is in agreement with a mixture model describing water as being composed of a limited number of water species (different ring structures or cluster types) that coexist in a temperature-and pressuredependent equilibrium [17]. On the other hand, the alternative continuum model implies that hydrogen bonds are equally distributed in the water sample, and that there is a continuous weakening of the hydrogen bonds with increasing temperature [18]. The presence of nearly-isosbestic points in the infrared spectra of water at different temperatures has usually been taken as support of the mixture model.…”

Role of hydration and water coordination in micellization of Pluronic block copolymers

“…Vibrational (infrared and Raman) spectroscopy is a useful technique for study of the effects of the local environment since the O-H stretching vibrations are correlated to the overall structure of water [20][21][22][23][24][25]. Water molecules in bulk water as well as in interacting water can display various hydrogen bonding interactions and orientations [26] that can result in several coordination types of water molecules (Fig.…”

“…Interaction of water with Pluronic macromolecules is viewed as a sum of the interactions of water with individual subunits (EO or PO), each subunit is considered separately and its hydration is viewed as a small solute hydration [1]. It is also proposed that conceptions based on the mixture models are more appropriate than continuous models for description of water interacting with or bound to polymer [21][22][23][24][25]. Our results do not indicate whether mixture or continuous models are more suitable for the liquid state of pure bulk water.…”

Hydrogen Bond Interactions Between Water Molecules in Bulk Liquid, Near Electrode Surfaces and Around Ions

“…Bernal and Fowler (Bernal & Fowler, 1933) suggested that molecules in liquid water are arranged in a tetrahedral manner, with each water molecule forming approximately four Hbonds with its nearest neighbors. Wall and Horing (Wall & Hornig, 1965) observed the Raman-scattering motions of the HDO molecules in H 2 O or D 2 O and concluded that liquid water does not have any significant fraction of unbonded molecules. Narten and Levy (Narten & Levy, 1969) supported the viewpoint that water molecules in liquid state are arranged in a predominantly tetrahedral geometry based on the observation that the mean separation between nearest neighbor molecules in ice and water are only marginally different.…”