Is photoisomerization required for NO photorelease in ruthenium nitrosyl complexes?

• Published in: Journal of molecular modeling Vol. 22; no. 11; pp. 284 - 10
• Main Authors: García, Juan Sanz, Alary, Fabienne, Boggio-Pasqua, Martial, Dixon, Isabelle M., Heully, Jean-Louis
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.11.2016; Springer Nature B.V; Springer Verlag (Germany)
• Subjects: Characterization and Evaluation of Materials; Chemical Sciences; Chemistry; Chemistry and Materials Science; Computer Appl. in Life Sciences; Computer Applications in Chemistry; Festschrift in Honor of Henry Chermette; Metastable state; Molecular Medicine; or physical chemistry; Original Paper; Potential energy; Ruthenium; Theoretical and; Theoretical and Computational Chemistry; Bond dissociation energy; DFT; Computational study; Nitrosyl; Photoisomerization pathway; Ruthenium complexes; Chain-of-states method; Photorelease
• ISSN: 1610-2940; 0948-5023
• DOI: 10.1007/s00894-016-3138-2

The factors that explain the competition between intramolecular NO linkage photoisomerization and NO photorelease in five ruthenium nitrosyl complexes were investigated. By applying DFT-based methods, it was possible to characterize the ground states and lowest triplet potential energy surfaces of these species, and to establish that both photoisomerization and photorelease processes can occur in the lowest triplet state of each species. This work highlights the crucial role of the sideways-bonded isomer, a metastable state also known as the MS2 isomer, in the photochemical loss of NO, while the results obtained also indicate that the population of the triplet state of this isomer is compulsory for both processes and show how photoisomerization and photorelease interfere. Graphical Abstract Illustration of the crucial role of the 3 MS2 state in the photoreactivities of ruthenium nitrosyl complexes