Proton momentum distribution in water: an open path integral molecular dynamics study

Area of Science:

• Quantum mechanics
• Computational chemistry
• Materials science

Background:

• Neutron Compton scattering experiments have measured proton momentum distributions in water.
• Theoretical calculations often employ path integral expressions to determine these distributions.

Purpose of the Study:

• To extend the staging path integral molecular dynamics method.
• To calculate proton momentum distributions in solid, liquid, and supercritical water phases.

Main Methods:

• Utilized an extended staging path integral molecular dynamics method.
• Employed a flexible, single point charge empirical force field for water interactions.
• Calculated proton momentum distributions across different water phases.

Main Results:

• The computed proton momentum distributions showed both agreement and discrepancies with experimental data.
• Differences between theoretical and experimental results were attributed to force field limitations.
• The study provides insights into proton environments and interactions within water.

Conclusions:

• The extended staging path integral molecular dynamics method is a viable approach for studying proton momentum distributions.
• Accurate force fields are crucial for precise theoretical predictions in condensed matter systems.
• Proton momentum distributions offer valuable information on molecular interactions and dynamics in water.