Theoretical Chemistry Accounts

, 136:135 | Cite as

The HSAB principle from a finite-temperature grand-canonical perspective

  • Ramón Alain Miranda-Quintana
  • Taewon David Kim
  • Carlos Cárdenas
  • Paul W. Ayers
Regular Article


We provide a new proof for Pearson’s hard/soft acid/base (HSAB) principle. Unlike alternative proofs, we do not presuppose a simplified parabolic dependence on the energy of the system with respect to changes in its number of electrons. Instead, we use the more physically grounded finite-temperature formulation of the grand-canonical ensemble. We show that under the usual assumptions regarding the chemical potentials and hardnesses of the involved species, the HSAB rule holds for a wide range of temperatures.


Conceptual DFT Hard/soft acid/base principle Finite-temperature Grand-canonical ensemble 



RAMQ, TDK, and PWA thank NSERC, the Canada Research Chairs, and Compute Canada for support. RAMQ acknowledges support from Foreign Affairs, Trade and Development Canada in the form of an ELAP scholarship. CC acknowledges support by FONDECYT (Grant 1140313), Financiamiento Basal para Centros Científicos y Tecnológicos de Excelencia-FB0807, and Project RC-130006 CILIS, Granted by the Fondo de Innovación para la Competitividad del Ministerio de Economía, Fomento y Turismo de Chile. Discussions with Laritza Domínguez and Cristina González are gratefully acknowledged.


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Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  • Ramón Alain Miranda-Quintana
    • 1
  • Taewon David Kim
    • 1
  • Carlos Cárdenas
    • 2
    • 3
  • Paul W. Ayers
    • 1
  1. 1.Department of Chemistry and Chemical BiologyMcMaster UniversityHamiltonCanada
  2. 2.Departamento de Física, Facultad de CienciasUniversidad de ChileSantiagoChile
  3. 3.Centro para el desarrollo de la Nanociencias y Nanotecnología, CEDENNASantiagoChile

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