Are One-Electron Bonds Any Different from Standard Two-Electron Covalent Bonds?

Area of Science:

• Theoretical Chemistry
• Quantum Mechanics
• Chemical Bonding Theory

Background:

• Traditional theories like valence bond and molecular orbital theory describe molecular properties but do not fully explain the origin of chemical bonds.
• Ruedenberg's work in the 1960s identified quantum interference between one-electron states as the cause of covalent bonds.

Purpose of the Study:

• To generalize and quantify the role of quantum interference in chemical bonding.
• To investigate the nature of one-electron bonds (2c1e) and compare them with conventional two-electron bonds (2c2e).

Main Methods:

• Development and application of the generalized product function energy partitioning (GPF-EP) method.
• Partitioning electronic density and energy into interference and quasi-classical contributions.
• Analysis of individual bonds within various molecules using GPF wave functions.

Main Results:

• Quantum interference is the dominant stabilizing factor for all analyzed chemical bonds, including single, double, triple, polar, and aromatic bonds.
• The GPF-EP method was extended to analyze bonds involving N electrons in M orbitals (N < M), specifically applied to (2c1e) bonds.
• One-electron bonds (2c1e) show no conceptual difference from conventional two-electron bonds (2c2e), as both arise from quantum interference.

Conclusions:

• Quantum interference is a universal phenomenon responsible for the stability of all chemical bonds.
• The concept of the chemical bond can be unified through the understanding of quantum interference.
• One-electron bonds are not unconventional but a fundamental manifestation of quantum interference in bonding.