Related Experiment Video
Updated: Aug 23, 2026

Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems
Published on: April 28, 2016
Effects of equilibrium H-bond distance and angle changes on Raman intensities from water
1Department of Chemistry, University of Kansas, Lawrence, Kansas 66045-0046, USA.
Abstract:
The H-bond energy dispersion over the inhomogeneously broadened OD stretching contour from dilute HDO in H(2)O was determined from absolute Raman intensities; it displays a large minimum near omega=2440 cm(-1) from short, strong H bonds (in agreement with the peak omega from lda ice) and a large maximum near 2650-2675 cm(-1) due to extremely weak or broken H bonds (in agreement with the peak omega from dense, supercritical HDO in H(2)O, 0.9 g/cm(3), 673 K). The difference between extrema is the maximum H-bond DeltaE, 5100+/-500 cal/mol, in excellent agreement with Pauling's limiting value. A pressure of 1500 bars yields an additional maximum and shoulder between the two dispersion extrema from pure water; saturated NaCl in water shows the additional maximum. The maxima near 3350 cm(-1) (1500 bar) or near 3360 cm(-1) (NaCl-H(2)O) arise from bent H bonds; 3350 cm(-1) (1500 bar) corresponding to an angle of approximately 170 degrees in the joint frequency/bend, probability of Lawrence and Skinner. Rising omega refers to a higher probability of larger O-O distances, bent H bonds, and H-bond weakening and breakage. A approximately 50-80 cm(-1) difference between the 2727 cm(-1) OD peak from HDO in steam, and the 2650-2675 cm(-1) dispersion maximum is explained via the very broad approximately 60 cm(-1) liquid peak observed at 342 degrees C and 2000 bar.
Related Concept Videos
IR Spectrum Peak Broadening: Hydrogen Bonding
However, the extent of hydrogen bonding influences the observed stretching frequency and band broadening. Intermolecular or intramolecular hydrogen bonding...
Raman Spectroscopy: Overview
However, a small fraction of the scattered light exhibits a frequency shift due to the exchange of energy between the incident photons and the...
IR Spectroscopy: Hooke's Law Approximation of Molecular Vibration
According to Hooke's law, the vibrational frequency is directly proportional to the...
IR Spectrum Peak Splitting: Symmetric vs Asymmetric Vibrations
¹H NMR of Conformationally Flexible Molecules: Temporal Resolution
¹H NMR of Labile Protons: Temporal Resolution
The –OH proton in alcohols typically appears in the range of δ 2 to 5 ppm but can vary depending on the specific...

