Autor según el artículo: Josep Casellas; Mar Reguero

Departamento: Química Física i Inorgànica

Autor/es de la URV: Reguero de la Poza, Maria del Mar

Palabras clave: Mecanismes de reacció Fotoquímica

Resumen: Phenalenone derivatives are involved in plant defense strategies, producing molecular singlet oxygen in a photosensitization process. Many experimental and theoretical studies determined that phenalenone (PN) can carry out this process with a quantum yield close to one. However, it has been observed that the efficiency of some of its derivatives is much lower. This is the case of 9-phenylphenalenone (9-PhPN). To elucidate the factors that determine the different photochemistry of PN and its derivate 9-PhPN, we have developed a CASSCF/CASPT2 study where several deactivation paths through the lowest excited states have been explored. We have found that the characteristics of the low-lying excited states are similar for both PN and 9-PhPN in the areas near the geometry of excitation. Consequently, the first processes that take place immediately after absorption are possible in both systems, including the population of the triplet state responsible for oxygen sensitization. However, 9-PhPN can also undergo cyclisation by a bond formation between the carbonyl oxygen and a carbon atom of the phenyl substituent. This process competes favourably with population of triplet states and is responsible for the decrease of the quantum yield of oxygen sensitization in 9-PhPN relative to PN.

Áreas temáticas: Química Physics, atomic, molecular & chemical Physical and theoretical chemistry Odontología Medicine (miscellaneous) Medicina ii Medicina i Materiais Interdisciplinar Geociências General medicine Farmacia Ensino Engenharias iv Engenharias iii Engenharias ii Ciências biológicas ii Ciências biológicas i Ciências ambientais Ciências agrárias i Chemistry, physical Biotecnología Biodiversidade Astronomia / física

Acceso a la licencia de uso: https://creativecommons.org/licenses/by/3.0/es/

ISSN: 15205215

Direcció de correo del autor: mar.reguero@urv.cat

Identificador del autor: 0000-0001-9668-8265

Página final: 821

Fecha de alta del registro: 2023-02-18

Volumen de revista: 122

Versión del articulo depositado: info:eu-repo/semantics/submittedVersion

Enlace a la fuente original: https://pubs.acs.org/doi/10.1021/acs.jpca.7b11569

URL Documento de licencia: http://repositori.urv.cat/ca/proteccio-de-dades/

Referencia al articulo segun fuente origial: Journal Of Physical Chemistry a. 122 (3): 811-821

Referencia de l'ítem segons les normes APA: Josep Casellas; Mar Reguero (2018). Photosensitization versus Photocyclization: competitive reactions of phenylphenalenone in its role as phytoanticipins in plant defense strategies. Journal Of Physical Chemistry a, 122(3), 811-821. DOI: 10.1021/acs.jpca.7b11569

DOI del artículo: 10.1021/acs.jpca.7b11569

Entidad: Universitat Rovira i Virgili

Año de publicación de la revista: 2018

Página inicial: 811

Tipo de publicación: Journal Publications