Ab initio molecular dynamics for molecules with variable numbers of electrons.

Area of Science:

• Computational Chemistry
• Quantum Mechanics
• Chemical Physics

Background:

• Accurate modeling of electron transfer is crucial for understanding chemical reactions.
• Existing methods often struggle to capture the dynamics of electron exchange with a reservoir at a fixed chemical potential.

Purpose of the Study:

• To extend the ab initio molecular dynamics method to incorporate electron exchange with a reservoir at a fixed chemical potential.
• To develop a robust computational approach for simulating redox dynamics.

Main Methods:

• Utilized a rigorously grand-canonical density functional approach.
• Employed separate potential energy surfaces for distinct oxidation states.
• Integrated these concepts into an ab initio molecular dynamics framework.

Main Results:

• The developed method successfully treats electron exchange between molecules and a reservoir.
• Demonstrated a discontinuous dependency of excess charge on chemical potential.
• This dependency aligns with statistical thermodynamics principles for equilibrium gas-phase reactions.

Conclusions:

• The extended ab initio molecular dynamics method provides a powerful tool for studying redox processes.
• The approach accurately captures the interplay between molecular dynamics and electronic states.
• Successfully applied to model the adiabatic redox dynamics of an aniline molecule.