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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization

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Understanding Chemical Selectivity through Well Selected Excited States.

F Guégan¹, T Pigeon², F De Proft³

¹IC2MP UMR 7285 , Université de Poitiers - CNRS, 4, rue Michel Brunet TSA, 51106-86073 Cedex 9, Poitiers , France.

The Journal of Physical Chemistry. A

|December 28, 2019

Summary

This summary is machine-generated.

We introduce new reactivity descriptors using perturbation theory to predict chemical reactions. Analyzing electron density changes reveals key insights into chemical selectivity and reactivity patterns.

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Area of Science:

Quantum Chemistry
Theoretical Chemistry
Computational Chemistry

Background:

Understanding chemical reactivity and selectivity is crucial in chemistry.
Existing methods for predicting reactivity can be computationally intensive.
Developing accurate and efficient descriptors is an ongoing challenge.

Purpose of the Study:

To propose novel reactivity and selectivity descriptors.
To derive these descriptors using Rayleigh-Schrödinger perturbation theory.
To analyze chemical systems under electrostatic perturbation.

Main Methods:

Utilizing Rayleigh-Schrödinger perturbation theory.
Analyzing first-order electron density polarization.
Examining second-order energy response and electron shifts.
Investigating the contribution of electronic excitations.

Main Results:

Developed new descriptors for reactivity and selectivity.
Qualitative reactivity insights from first-order polarization.
Quantitative selectivity information from second-order response and electron shifts.
Identified significant contributions from a limited number of electronic excitations.

Conclusions:

The proposed descriptors offer a new framework for understanding chemical reactivity.
Electron density reorganization upon excitation is a key indicator of reactivity.
This approach provides a potentially more efficient way to foresee chemical behavior.