Nuclear Quantum Effects in Water and Aqueous Systems: Experiment, Theory, and Current Challenges.

Area of Science:

• Physical Chemistry
• Quantum Mechanics
• Materials Science

Background:

• Nuclear quantum effects (NQE) profoundly influence hydrogen-bonded systems like water.
• The magnitude of NQE's impact on water properties varies significantly.
• Understanding NQE is crucial for accurately modeling water's behavior.

Purpose of the Study:

• To review recent advancements in the experimental, theoretical, and simulation-based study of NQE in water.
• To highlight novel techniques providing detailed insights into NQE's role.
• To explain the interplay of NQE and experimental observations.

Main Methods:

• Deep inelastic neutron scattering for experimental insights.
• Theoretical development of the principle of competing quantum effects.
• Advanced simulation algorithms incorporating NQE with on-the-fly electronic structure calculations.

Main Results:

• Novel experimental methods offer detailed views of NQE in water.
• The principle of competing quantum effects explains the dichotomy in water's isotope effects.
• Efficient simulation methods now allow for the inclusion of NQE.

Conclusions:

• Significant progress has been made in understanding NQE in water.
• The developed principles and methods enable accurate modeling of quantum effects.
• Future research opportunities lie in addressing current challenges in NQE studies.