The surprisingly high ligation energy of CO to Ruthenium porphyrins

Abstract : A combined theoretical and experimental approach has been used to investigate the binding energy of a ruthenium metalloporphyrin ligated with CO, ruthenium tetraphenyl porphyrin [Ru II TPP] in the Ru II oxidation degree. Measurements made by VUV ionization with the DESIRS beamline at Synchrotron SOLEIL lead to adiabatic ionization energies of [Ru II TPP] and its complex with CO, [Ru II TPP-CO], to be 6.48±0.03 eV and 6.60±0.03 eV, respectively while the ion dissociation threshold of [Ru II TPP-CO] + is measured at 8.36±0.03 eV. These experimental data are used to derive binding energies of the CO ligand in the neutral and cationic complex (1.88±0.06 eV and 1.76±0.06 eV, respectively) using a Born-Haber cycle. Density Functional Theory calculations, in very satisfactory agreement with the experimental results, help to get insights into the metal-ligand bond. Notably, the high ligation energies can be rationalized in terms of the ruthenium orbital structure, which is singular from that of the iron atom. Thus, beyond indications of a strengthening of the Ru-CO bond from the decrease in the CO vibrational frequency in the complex as compared to the Fe-CO bond, high level calculations are essential to describe accurately the metal ligand (CO) bond and show that the Ru-CO bond energy is strongly affected by the splitting of triplet and singlet spin states in uncomplexed [Ru TPP].
Type de document :
Article dans une revue
Physical Chemistry Chemical Physics, Royal Society of Chemistry, 2018, 20 (17), pp.11730-11739. 〈10.1039/C8CP01190G〉
Liste complète des métadonnées

https://hal.archives-ouvertes.fr/hal-01891524
Contributeur : Caroline Lebe <>
Soumis le : mardi 9 octobre 2018 - 16:36:21
Dernière modification le : samedi 13 octobre 2018 - 01:17:04

Fichiers

RUTTP_CO_20Fevrier-NS-1.pdf
Fichiers produits par l'(les) auteur(s)

Identifiants

Citation

Niloufar Shafizadeh, Séverine Boyé-Péronne, Satchin Soorkia, Barbara Cunha de Miranda, Gustavo Garcia, et al.. The surprisingly high ligation energy of CO to Ruthenium porphyrins. Physical Chemistry Chemical Physics, Royal Society of Chemistry, 2018, 20 (17), pp.11730-11739. 〈10.1039/C8CP01190G〉. 〈hal-01891524〉

Partager

Métriques

Consultations de la notice

67

Téléchargements de fichiers

37