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Related Experiment Video

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Direct Imaging of Laser-driven Ultrafast Molecular Rotation

Direct Imaging of Laser-driven Ultrafast Molecular Rotation

Published on: February 4, 2017

Excited state radiationless decay process with Duschinsky rotation effect: formalism and implementation.

Qian Peng¹, Yuanping Yi, Zhigang Shuai

¹Key Laboratory of Organic Solids, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, 100080 Beijing, People's Republic of China.

The Journal of Chemical Physics

|March 27, 2007

Summary

This study introduces a new analytic method to calculate internal conversion rates in complex molecules, accounting for the Duschinsky rotation effect. The approach provides a more accurate understanding of excited-state dynamics and molecular processes.

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Area of Science:

Physical Chemistry
Theoretical Chemistry
Computational Chemistry

Background:

Characterizing differences between ground and excited state potential energy surfaces is crucial for understanding molecular dynamics.
The harmonic oscillator model is a practical approach for describing excited-state dynamics in complex molecules.
The Duschinsky rotation effect describes the difference in vibrational modes between electronic states.

Purpose of the Study:

To derive an analytic formalism for calculating internal conversion rates.
To incorporate the Duschinsky rotation effect into the calculation of internal conversion rates.
To provide a method applicable to multimode mixing in complex molecules.

Main Methods:

Application of first-order perturbation theory (Fermi's golden rule).
Utilizing path integrals of Gaussian type for the correlation function.
Development of an analytic formalism for internal conversion rate calculations.

Main Results:

An analytic expression for calculating internal conversion rates with Duschinsky rotation was derived.
The formalism was validated by comparison with previous analytical and numerical studies.
The method was successfully applied to ethylene molecules with two-mode mixing.

Conclusions:

The developed formalism accurately calculates internal conversion rates, including the Duschinsky rotation effect.
This method offers a practical and effective way to study excited-state dynamics in complex molecular systems.
The approach is suitable for multimode mixing scenarios, enhancing theoretical chemistry capabilities.