Core-ionization spectrum of liquid water

Area of Science:

• Physical Chemistry
• Quantum Chemistry
• Spectroscopy

Background:

• Experimental determination of ionization energies for solvated species is complex.
• Challenges include surface potential, electrolyte effects, and finite photoelectron escape depths.

Purpose of the Study:

• To obtain robust theoretical values for the intrinsic bulk ionization energy of water.
• To quantify the solvent-induced shift in water's core-ionization spectrum.

Main Methods:

• State-of-the-art calculations utilizing coupled-cluster theory.
• Application of electrostatic embedding theoretical protocols.

Main Results:

• The intrinsic solvent-induced shift for the 1s_O ionization energy of water was calculated to be -1.79 eV.
• Computed absolute position and width of the 1s_O peak are 538.47 eV and 1.44 eV, respectively.
• Results show good agreement with experimental data.

Conclusions:

• The theoretical protocols provide accurate predictions for water's core-ionization spectrum.
• This work offers reliable theoretical benchmarks for experimental studies.