Article
2021

Relationship between Atomic Structure and Electrochemistry. 2. Influence of pH and Ligand Field on the Gibbs Free Energy of Oxidation ΔG0,Ox


J. A. Díaz-Ponce J. A. Díaz-Ponce , A. Campero A. Campero
Russian Journal of Electrochemistry
https://doi.org/10.1134/S1023193520120058
Abstract / Full Text

In this work it is found that the HOMO–LUMO gap, formed after the electron is added to bond the ligand and the transition metal, determines the stability and the power of reduction of the metal complex. In order to establish this relationship, we have used the values of the Gibbs energy of oxidation in water at pH 0 for different ligands in which the same number of electrons are transferred. We have also used diagrams of molecular orbitals for metal complexes of Ta, Re, Pt and Au. This relationship is based on the higher probability of electronic transition between orbitals with a lower HOMO–LUMO gap.

Author information
  • Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa. Col. Vicentina, Apdo. Post. 55-534, D.F., C.P. 09340, México, México

    J. A. Díaz-Ponce

  • Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa. Col. Vicentina, Apdo. Post. 55-534, D.F., C.P. 09340, México, México

    A. Campero

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