Structure and torsional dynamics of the water octamer from THz laser spectroscopy near 215 mm
- Author(s): Cole, WTS
- Farrell, JD
- Wales, DJ
- Saykally, RJ
- et al.
Published Web Locationhttps://doi.org/10.1126/science.aad8625
Clusters of eight water molecules play an important role in theoretical analysis of aqueous structure and dynamics but have proven to be challenging experimental targets. Here we report the high-resolution spectroscopic characterization of the water octamer. Terahertz (THz) vibration-rotation-tunneling (VRT) spectroscopy resolved 99 transitions with 1 part per million precision in a narrow range near 46.5 wave numbers, which were assigned to the h16octamer via detailed isotope dilution experiments. Fitting to a semirigid symmetric top model supports predictions of two coexisting cuboidal structures and provides precise values for the changes in their rotational constants. Comparison with theory and previous spectroscopic data provides a characterization of the two structures and the observed torsional vibration and supports the prediction that the D2dsymmetry structure is lower in energy than the S4isomer.
Many UC-authored scholarly publications are freely available on this site because of the UC Academic Senate's Open Access Policy. Let us know how this access is important for you.