Dynamics of the Bulk Hydrated Electron from Many-Body Wave-Function Theory

Area of Science:

• Physical Chemistry
• Computational Chemistry
• Chemical Physics

Background:

• The structure of the hydrated electron remains elusive due to its short lifetime and low concentration.
• Experimental observation is challenging, leading to ongoing debate about its molecular arrangement.

Purpose of the Study:

• To provide conclusive evidence for the structural model of the bulk hydrated electron.
• To investigate the formation dynamics and properties of the hydrated electron in liquid water.

Main Methods:

• First molecular dynamics simulation of the bulk hydrated electron.
• Utilized correlated wave-function theory for high-accuracy calculations.
• Analyzed cavity formation, H-H bond characteristics, and spectroscopic signatures.

Main Results:

• Conclusive evidence for a persistent tetrahedral cavity formed by four water molecules.
• Demonstrated the absence of stable non-cavity structures.
• Observed rapid cavity formation (<1 picosecond) with intermediate less-regular cavities.
• Correlated cavity structure with H-H bonds and distinct spectroscopic signatures.
• Simulated negative spin density and gyration radius matching experimental data.

Conclusions:

• The hydrated electron predominantly exists within a stable tetrahedral water cavity.
• Simulation results align with experimental observations, resolving structural ambiguities.
• The study provides a detailed molecular-level understanding of the hydrated electron.