title: Exploration of Excited State Deactivation Pathways of Adenine Monohydrates.
abstract: Binding of a single water molecule has a dramatic effect on the excited state lifetime of adenine. Here we report a joint nonadiabatic dynamics and reaction paths study aimed at understanding the sub-100 fs lifetime of adenine in the monohydrates. Our nonadiabatic dynamics simulations, performed using the ADC(2) electronic structure method, show a shortening of the excited state lifetime in the monohydrates with respect to bare adenine. However, the computed lifetimes were found to be significantly longer that the observed one. By comparing the reaction pathways of several excited state deactivation processes in adenine and adenine monohydrates, we show that electron-driven proton transfer from water to nitrogen atom N3 of the adenine ring may be the process responsible for the observed ultrafast decay. The inaccessibility of the electron-driven proton transfer pathway to trajectory-based nonadiabatic dynamics simulation is discussed.
authors.affiliation: Ruđer Bošković Institute , Bijenička 54, 10000 Zagreb, Croatia.
authors.forename: Sermsiri
authors.initials: S
authors.lastname: Chaiwongwattana
authors.affiliation: Ruđer Bošković Institute , Bijenička 54, 10000 Zagreb, Croatia.
authors.forename: Marin
authors.initials: M
authors.lastname: Sapunar
authors.affiliation: Ruđer Bošković Institute , Bijenička 54, 10000 Zagreb, Croatia.
authors.forename: Aurora
authors.initials: A
authors.lastname: Ponzi
authors.affiliation: Dipartimento di Scienze Chimiche, Università di Trieste , 34127 Trieste, Italy.
authors.forename: Piero
authors.initials: P
authors.lastname: Decleva
authors.affiliation: Ruđer Bošković Institute , Bijenička 54, 10000 Zagreb, Croatia.
authors.forename: Nađa
authors.initials: N
authors.lastname: Došlić
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D011789:Quantum Theory; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water; D000225:Adenine