A Comparison of Partial Atomic Charges for Electronically Excited States

Area of Science:

• Quantum Chemistry
• Computational Chemistry
• Chemical Physics

Background:

• Partial atomic charges offer insights into molecular properties and reaction mechanisms.
• Their application to excited-state electronic structure remains underexplored.

Purpose of the Study:

• To evaluate established partial atomic charge methods for excited states.
• To demonstrate the utility of real-space charges in interpreting excited-state electron transfer.
• To investigate electronic structures near conical intersections in polyenes.

Main Methods:

• Assessment of well-established partial atomic charge calculation methods.
• Analysis of interatomic, intermolecular, and interbond electron transfer in excited states.
• Application to conjugated polyenes and conical intersection regions.

Main Results:

• Partial atomic charges effectively interpret electronic structures in excited-state processes.
• Analogous electronic structures are observed near conical intersections in polyenes.
• The iterative Hirshfeld approach yields chemically intuitive and transferable results.

Conclusions:

• Real-space partial atomic charges are useful for characterizing excited-state electronic structure.
• The iterative Hirshfeld method is a reliable approach for excited-state charge analysis.
• This method aids in understanding photochemical processes and molecular systems.