Per-Olov Lowdin and the Coulomb Hamilton: Implications for Definition of Atoms and Bonds in Molecules

Abstract

In later papers,1,2 Per-Olov Lowdin addressed the issue of devising a satisfactory mathematical definition of molecular structure with characteristic clarity and insight, placing earlier related studies in the context of a common unifying perspective. He particularly noted the apparent impossibility of meaningful assignments of indistinguishable electrons to particular atomic nuclei in a molecular Hamiltonian, and the consequent absence of atoms, isomers, and spatial molecular symmetries on this basis. In this contribution we address the assignments of electrons to atoms in molecules and provide a meaningful definition of chemical bonds between atoms from the perspective of representation theory. Use of an orthonormal (Eisenschitz-London) outer product of atomic spectral eigenstates as a representational basis in the absence of over-all aggregate electron antisymmetric allows meaningful assignments of electrons to particular atomic nuclei. Adiabatic (Born-Oppenheimer) molecular energies are obtained in this way in the form of a sum of physically significant atomic promotion energies and a pairwise-atomic sum of interaction energies, providing a quantum-mechanically-based quantitative definition of atoms and chemical bonds in molecules.

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Document Details

Document Type
Technical Report
Publication Date
May 20, 2014
Accession Number
AD1181970

Entities

People

  • G G Gallup
  • J. A. Boatz
  • J. D. Mills
  • P. W. Langhoff

Organizations

  • Air Force Research Laboratory
  • University of California, San Diego
  • University of Nebraska–Lincoln

Tags

DTIC Thesaurus Topics

  • Air Force
  • Air Force Research Laboratories
  • Applied Mathematics
  • Atoms
  • Charge Transfer
  • Chemical Bonds
  • Chemistry
  • Electrons
  • Energy
  • Ground State
  • Materials
  • Mathematics
  • Military Research
  • Molecules
  • Physics
  • Potential Energy
  • Quantum Chemistry
  • Quantum Mechanics
  • Subatomic Particles
  • Symmetry
  • Universities

Fields of Study

  • Physics

Readers

  • Linear Algebra
  • Quantum Chemistry
  • Theoretical Analysis.

Technology Areas

  • Microelectronics
  • Quantum Computing