Raman Spectroscopy of Liquid Interactions

Raman spectroscopy exploits the inelastic scattering of monochromatic light to probe molecular vibrations and intermolecular dynamics in liquids. By analysing frequency shifts of scattered photons, it reveals both intramolecular bond stretches and low-frequency collective motions arising from hydrogen bonding, solvation shells and transient aggregates. Advances in ultrafast laser techniques and multidimensional approaches, including terahertz–Raman coupling, have enabled the correlation of distinct vibrational modes to map anharmonic couplings and energy-transfer pathways. These insights inform our understanding of hydrogen-bond rearrangements in water, solvent-dependent shifts in carbonyl vibrations and the formation and dissociation of molecular clusters. Low-frequency measurements elucidate librational motions and collective modes, underpinning models of local order and dielectric response. Integration with molecular dynamics simulations is increasingly translating spectral features into detailed pictures of liquid-phase structure and dynamics, with implications for optimising reaction media, designing functional materials and characterising biological environments.

Research from Nature Portfolio

Recent studies have applied two-dimensional infrared–Raman spectroscopy to liquid water, combining equilibrium–nonequilibrium molecular dynamics with spectrum decomposition to link the tetrahedral order of the hydrogen-bond network to specific cross-peaks in the multidimensional spectrum. This work clarifies how temperature modulates the coupling between low-frequency intermolecular modes and high-frequency intramolecular O–H stretches. In complementary research on acetone isolated in an inert matrix, high-resolution isotropic and anisotropic Raman spectra were paired with first-principles calculations to elucidate the noncoincidence effect of the C=O stretching mode across monomer, dimer and trimer forms. An aggregated-structure model emerged, demonstrating controllable monomer–aggregate equilibria via thermal annealing and offering a blueprint for understanding concentration-dependent spectral shifts.

Raman Spectroscopy of Liquid Interactions publication trend

The graph below shows the total number of articles in raman spectroscopy of liquid interactions across all publications each year (not limited to Nature Index journals).

Technical terms

Raman Spectroscopy: Technique based on inelastic scattering of light by molecules to probe vibrational energy levels.

Two-Dimensional Spectroscopy: Multidimensional approach correlating sequential light–matter interactions to reveal coupling between vibrational modes.

Noncoincidence Effect: Shift between isotropic and anisotropic Raman band positions due to intermolecular interactions.

Cross Peak: Off-diagonal feature in a two-dimensional spectrum indicating coupling between distinct vibrational modes.

Covariance-Based Detection: Analysis of statistical correlations in noisy probe signals to extract spectroscopic information.

Tetrahedral Order: Measure of the local arrangement of hydrogen bonds in water reflecting deviations from an ideal tetrahedral geometry.

References

1. Two-dimensional infrared-Raman spectroscopy as a probe of water’s tetrahedrality. Nature Communications (2023).
2. Study on the noncoincidence effect phenomenon using matrix isolated Raman spectra and the proposed structural organization model of acetone in condense phase. Scientific Reports (2017).
3. Transient measurement of phononic states with covariance-based stochastic spectroscopy. Light: Science & Applications (2022).
4. Low-frequency anharmonic couplings in bromoform revealed from 2D Raman-THz spectroscopy: From the liquid to the crystalline phase. The Journal of Chemical Physics (2022).
5. Study of Raman Scattering of Light in Liquid Arenes and Their Halogen-Substituted ones in the Low-Frequency Region of the Spectrum. Proceedings of the Southwest State University Series Engineering and Technologies (2024).