Skip to main content
padlock icon - secure page this page is secure

Physical Basis and Limitations of Equalization Rules and Principles: Valence-State Electronegativity and Valence-Pair-Affinity versus Operational Chemical Potential

Buy Article:

$106.22 + tax (Refund Policy)

The postulated identity of the operational chemical potential, μ, with the negative of the ground-state electronegativity, μ = –X GS, is a cornerstone of conceptual DFT (cDFT). However, a trend has developed to overestimate the applicability and accuracy of the corresponding equalization principles. The operational molecular μ mol in general does not result from equalizing atomic μ at values. Frequent violations of the strict Wigner-Witmer symmetry rules by cDFT cause μ molμ at in homonuclear diatoms. Consequently the previous general proofs of the chemical potential equalization (CPE) principle and its equivalence to the electronegativity equalization (ENE) principle seem inadequate. Such fundamental limitations of cDFT need to be addressed, and solutions proposed also in connection with violations of the variational principle due to electron-self-interaction errors. Mulliken's valence-state definition of electronegativity, χVS, intrinsically fulfils the Wigner-Witmer rules, and ENE by χVS is surprisingly accurate for homonuclear diatoms. For polar bonds a charge dependent generalization of Mulliken's χVS is introduced as “Valence-Pair-Affinity,” VPA. It is consistently derived from Ruedenberg's theory of the chemical bond and does neither violate the variational principle nor the Wigner-Witmer rules. VPA is locally equilibrated in 2-center electron-pair bonds, but not in the whole molecule. The partial atomic charges obtained by VPA equilibration are consistent and agree well with those obtained by Natural Bond Orbital population analysis and the ones found in Klopman's “equipotential orbitals.”
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Article Media
No Metrics

Keywords: BOND POLARITY; CHEMICAL POTENTIAL; CONCEPTUAL DFT; ELECTRONEGATIVITY EQUALIZATION; EQUALIZATION PRINCIPLES; MULLIKEN VALENCE STATE; PARTIAL CHARGE; RUEDENBERG VALENCE STATE; VALENCE-PAIR-AFFINITY; WIGNER-WITMER SYMMETRY RULES

Document Type: Review Article

Publication date: February 1, 2015

More about this publication?
  • QUANTUM MATTER is a peer-reviewed interdisciplinary journal consolidating research activities in all theoretical, experimental and technological aspects dealing with fundamental structure of matter from cosmology to materials science.
  • Editorial Board
  • Information for Authors
  • Subscribe to this Title
  • Ingenta Connect is not responsible for the content or availability of external websites
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more