A tutorial for understanding chemical reactivity through the valence bond approach

Area of Science:

• Quantum Chemistry
• Chemical Kinetics
• Biochemistry

Background:

• Valence Bond (VB) diagrams offer a visual approach to understanding chemical bonding and reactivity.
• Hydrogen Atom Transfer (HAT) is a fundamental reaction mechanism in chemistry and biology.
• Predicting reaction barriers is crucial for understanding reaction rates and mechanisms.

Purpose of the Study:

• To provide a tutorial on constructing and utilizing Valence Bond (VB) diagrams for chemical reactivity analysis.
• To demonstrate the application of VB diagrams in estimating Hydrogen Atom Transfer (HAT) reaction barriers.
• To illustrate the unifying principles of reactivity treatments using VB diagrams.

Main Methods:

• Step-by-step guide on constructing VB diagrams for various reactions.
• Methodology for estimating HAT barriers from raw experimental or computational data.
• Application of VB diagrams to model reactions ranging from H + H2 to enzymatic HAT in cytochrome P450.

Main Results:

• Demonstrated construction of VB diagrams for diverse chemical reactions.
• Provided a practical method for estimating HAT barriers using VB diagrams.
• Highlighted the applicability of VB diagrams across different chemical systems, including biological enzymes.

Conclusions:

• VB diagrams are a powerful tool for gaining insight into chemical reactivity.
• The methodology presented allows for both quantitative estimation of HAT barriers and qualitative understanding of reaction mechanisms.
• This tutorial promotes a unified approach to studying chemical reactivity, combining theoretical insight with numerical data.