Photoinduced electron-driven proton transfer from water to an N-heterocyclic chromophore: nonadiabatic dynamics studies for pyridine–water clusters

We performed the excited-state dynamics simulations for pyridine–water clusters and found the more water molecules involved in the cluster, the higher efficiency the water-splitting reaction has, which is qualitatively in consistent with a recent gas-phase experimental observations.

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Photorelaxation of imidazole and adenine via electron-driven proton transfer along H2O wires

Faraday Discussions ◽

10.1039/c6fd00131a ◽

2016 ◽

Vol 195 ◽

pp. 237-251 ◽

Cited By ~ 11

Author(s):

Rafał Szabla ◽

Robert W. Góra ◽

Mikołaj Janicki ◽

Jiří Šponer

Keyword(s):

Molecular Dynamics ◽

Excited State ◽

Potential Energy ◽

Proton Transfer ◽

Potential Energy Surface ◽

Molecular Dynamics Simulations ◽

Gas Phase ◽

Energy Surface ◽

Water Molecules ◽

Dynamics Simulations

Photochemically created πσ* states were classified among the most prominent factors determining the ultrafast radiationless deactivation and photostability of many biomolecular building blocks. In the past two decades, the gas phase photochemistry of πσ* excitations was extensively investigated and was attributed to N–H and O–H bond fission processes. However, complete understanding of the complex photorelaxation pathways of πσ* states in the aqueous environment was very challenging, owing to the direct participation of solvent molecules in the excited-state deactivation. Here, we present non-adiabatic molecular dynamics simulations and potential energy surface calculations of the photoexcited imidazole–(H2O)5 cluster using the algebraic diagrammatic construction method to the second-order [ADC(2)]. We show that electron driven proton transfer (EDPT) along a wire of at least two water molecules may lead to the formation of a πσ*/S0 state crossing, similarly to what we suggested for 2-aminooxazole. We expand on our previous findings by direct comparison of the imidazole–(H2O)5 cluster to non-adiabatic molecular dynamics simulations of imidazole in the gas phase, which reveal that the presence of water molecules extends the overall excited-state lifetime of the chromophore. To embed the results in a biological context, we provide calculations of potential energy surface cuts for the analogous photorelaxation mechanism present in adenine, which contains an imidazole ring in its structure.

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Effects of the second hydration shell on excited-state multiple proton transfer: dynamics simulations of 7-azaindole:(H2O)1–5 clusters in the gas phase

Theoretical Chemistry Accounts ◽

10.1007/s00214-014-1480-y ◽

2014 ◽

Vol 133 (5) ◽

Cited By ~ 8

Author(s):

Nawee Kungwan ◽

Khanittha Kerdpol ◽

Rathawat Daengngern ◽

Supa Hannongbua ◽

Mario Barbatti

Keyword(s):

Excited State ◽

Proton Transfer ◽

Gas Phase ◽

Hydration Shell ◽

Dynamics Simulations

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Excited-state intramolecular proton transfer to carbon atoms: nonadiabatic surface-hopping dynamics simulations

Physical Chemistry Chemical Physics ◽

10.1039/c5cp00101c ◽

2015 ◽

Vol 17 (15) ◽

pp. 9687-9697 ◽

Cited By ~ 40

Author(s):

Shu-Hua Xia ◽

Bin-Bin Xie ◽

Qiu Fang ◽

Ganglong Cui ◽

Walter Thiel

Keyword(s):

Electronic Structure ◽

Excited State ◽

Proton Transfer ◽

Intramolecular Proton Transfer ◽

Nonadiabatic Dynamics ◽

Surface Hopping ◽

Dynamics Simulations

The combined electronic structure computations and nonadiabatic dynamics simulations show that excited-state intramolecular proton transfer to carbon atoms can be ultrafast.

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