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One-electron bonds are not "half-bonds"
David Wilian Oliveira de Sousa1, Marco Antonio Chaer Nascimento
1Instituto de Química, Universidade Federal do Rio de Janeiro Cidade Universitária, CT Bloco A Sala 412, Rio de Janeiro, RJ 21941-909, Brazil. chaer01@gmail.com.
Physical Chemistry Chemical Physics : PCCP
|June 12, 2019
Summary
Quantum interference explains chemical bonds. This study extends interference energy analysis (IEA) to one-electron bonds, confirming interference as the dominant effect and reinforcing its central role in chemical bonding theory.
Area of Science:
- Quantum Chemistry
- Chemical Bonding Theory
Background:
- Molecular Orbital (MO) and Valence-Bond (VB) models describe electronic structure but not the fundamental nature of chemical bonds.
- Ruedenberg's work identified quantum interference as the origin of chemical bonds in two-electron systems.
Purpose of the Study:
- To test the generality of quantum interference as the cause of chemical bonds.
- To extend Interference Energy Analysis (IEA) to analyze two-center one-electron (2c-1e) bonds.
- To investigate the role of quantum interference in one-electron chemical bonds.
Main Methods:
- Developed a powerful Interference Energy Analysis (IEA) method.
- Extended IEA to analyze two-center one-electron (2c-1e) bonds using Generalised Product Functions (GPF) from spin-coupled wave functions (SC(N,M)).
- Analyzed diatomic and polyatomic molecules, comparing 2c-1e bonds with analogous 2c-2e bonds.
Main Results:
- Demonstrated that two-electron bonds, regardless of polarity, arise from quantum interference.
- Showed that quantum interference is the dominant effect in two-center one-electron bonds.
- Confirmed the universal role of quantum interference in chemical bonding across different bond types.
Conclusions:
- Quantum interference is the fundamental origin of all chemical bonds, including one-electron bonds.
- The Interference Energy Analysis (IEA) is a versatile method for quantifying bonding contributions.
- This work reinforces quantum interference as the central concept in chemical bonding theory.
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