Related Experiment Video
Updated: Sep 20, 2025

Author Spotlight: Advancing Cellular and Protein Engineering to Control Biological Functions and Develop Novel Therapies
Published on: September 27, 2024
Excited state deactivation mechanisms of protonated adenine: a theoretical study
Leila Shahrokh1, Reza Omidyan1, Gholamhassan Azimi1
1Department of Chemistry, University of Isfahan, 81746-73441, Isfahan, Iran. r.omidyan@sci.ui.ac.ir.
Abstract:
The quantum chemical computational method and Born-Oppenheimer (BO) dynamics simulation were employed to investigate the non-radiative relaxation mechanism of protonated 9H- and 7H-adenine (AH+). We located three conical intersections (CIs) between the first 1ππ* excite state and the S0 ground state potential energy surfaces for the two most stable protonated isomers of adenine. It was predicted that the barrier-free potential energy profile along the out-of-plane deformation coordinates of the six-member ring plays the most prominent role in the deactivation of the excited AH+ from 1ππ* to the ground state via ultrafast internal conversions. This ring deformation was predicted to provide a common deactivation pathway in protonated DNA/RNA bases, describing their high level of photostability, and corresponding neutral homologues.
More Related Videos
15:05Deciphering the Structural Effects of Activating EGFR Somatic Mutations with Molecular Dynamics Simulation
Published on: May 20, 2020
10:52Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
Related Concept Videos
Deactivation Processes: Jablonski Diagram
Aldehydes and Ketones with Amines: Enamine Formation Mechanism
Basicity of Aliphatic Amines
To measure the basicity of amines, two conventions are generally used. The first defines Kb as the basicity constant for the deprotonation reaction of water by the amine, as presented in Figure 1. Conventionally, lower Kb indicates...
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism
Hydrolysis of ATP
If one phosphate group is removed, a molecule of ADP—adenosine diphosphate—remains, along with inorganic phosphate. ADP can be further hydrolyzed to AMP—adenosine...
Basicity of Heterocyclic Aromatic Amines