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Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
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Tunnelling splitting patterns in some partially deuterated water trimers
Mihael Eraković1, Marko T Cvitaš1
1Department of Physical Chemistry, Ruđer Bošković Institute, 10000 Zagreb, Croatia. mcvitas@irb.hr.
Physical Chemistry Chemical Physics : PCCP
|February 15, 2021
Summary
We characterized tunnelling splitting patterns in partially deuterated water trimers using a new semiclassical method. Our findings reveal complex splitting patterns explained by rearrangement and bifurcation dynamics, aiding future spectral analysis.
Area of Science:
- Quantum Chemistry
- Spectroscopy
- Molecular Dynamics
Background:
- Understanding molecular dynamics in hydrogen-bonded clusters is crucial for interpreting experimental spectra.
- Partially deuterated water clusters present complex quantum effects due to isotopic substitution.
- Tunnelling splitting (TS) provides insights into molecular rearrangements and vibrational states.
Purpose of the Study:
- To characterize the ground-state tunnelling splitting (TS) patterns of partially deuterated water trimers.
- To apply a novel semiclassical method for calculating TS in asymmetric systems.
- To elucidate the influence of isotopic substitution and bifurcation dynamics on TS patterns.
Main Methods:
- Development and application of a semiclassical method for calculating tunnelling splittings (TS).
- Analysis of ground-state TS patterns in partially deuterated water trimers: (D2O)(H2O)2, (H2O)(D2O)2, (HOD)(H2O)2, and (HOD)(D2O)2.
- Computation of TS patterns using distinct tunnelling matrix elements and derivation of analytic expressions for bifurcation splittings.
Main Results:
- Characterized ground-state TS patterns for partially deuterated water trimers, revealing sextets due to rearrangement mechanisms.
- Observed complex fine structures in TS patterns attributed to bifurcation dynamics, resulting in quartets of doublets or doublets of quartets.
- Identified distinct TS patterns for in-bond and out-of-bond substituted isomers in (HOD)-containing trimers.
Conclusions:
- The developed semiclassical method effectively characterizes TS patterns in asymmetric, partially deuterated water trimers.
- Tunnelling dynamics, including rearrangement and bifurcation, significantly influence the observed spectral patterns.
- The approach is applicable to other water clusters and excited vibrational states, aiding experimental spectral assignment.
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