The solvation shell probed by resonant intermolecular Coulombic decay.

Area of Science:

• Physical Chemistry
• Chemical Physics
• Spectroscopy

Background:

• Solvation shell molecules exhibit unique properties compared to bulk solvents, influencing chemical reactivity.
• Traditional X-ray spectroscopies often struggle to selectively probe these specific solvation shell molecules.
• Intermolecular Coulombic decay (ICD) and related X-ray triggered non-local processes offer potential for selective probing.

Purpose of the Study:

• To explore resonant intermolecular Coulombic decay (ICD) in aqueous solutions.
• To demonstrate the capability of ICD to characterize the first solvation shell of excited solvated cations.
• To establish ICD as a powerful spectroscopic tool for probing solvation shell properties.

Main Methods:

• Application of electron spectroscopy to aqueous solutions.
• Investigation of resonant intermolecular Coulombic decay (ICD) processes.
• Utilizing X-ray triggered non-local decay mechanisms for selective probing.

Main Results:

• Resonant ICD processes were successfully applied to study solvated cations in aqueous solutions.
• One ICD pathway was identified as a sensitive marker for ion pair formation.
• Another ICD pathway provided direct measurement of electron binding energies for first solvation shell water molecules.

Conclusions:

• Resonant intermolecular Coulombic decay (ICD) is a powerful and selective spectroscopic technique.
• ICD offers direct access to previously elusive properties of solvation shell molecules, such as electron binding energies.
• This method provides new avenues for understanding solvation dynamics and ion-solvent interactions.