Using density based indexes to characterize excited states evolution.

Area of Science:

• Computational Chemistry
• Photochemistry
• Quantum Mechanics

Background:

• Understanding excited-state processes is crucial for designing new photochemical compounds.
• Existing computational tools for predicting decay channels can be complex and computationally expensive.
• The density-based index (Π) was previously used for first excited state to ground state decay.

Purpose of the Study:

• To evaluate the capability of the density-based index (Π) in identifying decay channels between higher and lower excited states.
• To demonstrate the utility of the Π index as a computational tool for describing photochemical reactions.
• To assess the potential of the Π index for designing novel chemical compounds.

Main Methods:

• Application of the density-based index (Π) to two well-characterized model systems.
• Evaluation of the index based on energetics and electron densities of involved electronic states.
• Coupling the Π index with quantum methods providing excited-state densities.

Main Results:

• The Π index successfully identified regions prone to excited-state decay in both model systems.
• The index proved proficient in predicting decay pathways between different excited states.
• The computational cost of using the Π index is minimal.

Conclusions:

• The density-based index (Π) is a valuable and efficient computational tool for predicting excited-state decay channels.
• The Π index shows significant potential for applications in the rational design of new chemical compounds.
• This descriptor offers a simple yet powerful method for analyzing photochemical processes.