Picosecond dynamics of a small molecule in aqueous solution probed by PAC spectroscopy
Abstract
111 Ag PAC spectroscopy was applied to explore the rapid dynamics of a small, inorganic probe in water/sucrose solutions with viscosity, ξ , from 1 to 121 mPa∙s at 9 °C or 20 °C. The measured characteristic timescale does not scale linearly with ξ/T , as predicted by the Stokes–Einstein–Debye model for the rotational correlation time, and power-law scaling is also unsatisfactory. In contrast, a model that incorporates local probe-site dynamics on a ~ 400 ps timescale describes the data well. This is the first indication that PAC spectroscopy can resolve both rotational diffusion and picosecond local dynamics via their different ξ/T scaling.
Fields of Study & Subjects
Spectroscopy and Quantum Chemical Studies
Photochemistry and Electron Transfer Studies
Molecular Spectroscopy and Structure
Publication details
- Journal / source
- Chemical Physics Letters
- Volume
- 890
- Pages
- 142747–142747
- Publication date
- 5 March 2026
- Language
- EN