Excited-state lifetime of adenine near the first electronic band origin

Abstract

The excited-state lifetime of supersonically cooled adenine was measured in the gas phase by femtosecond pump-probe transient ionization as a function of excitation energy between 36 100 and 37 500cm(-1). The excited-state lifetime of adenine is ∼2ps around the 0-0 band of the (1)L(b) ππ(∗) state (36 105cm(-1)). The lifetime drops to ∼1ps when adenine is excited to the (1)L(a) ππ(∗) state with the pump energy at 36 800cm(-1) and above. The excited-state lifetimes of (1)L(a) and (1)L(b) ππ(∗) states are differentiated in accordance with previous frequency-resolved and computational studies.

Ultrafast non-radiative decay of gas-phase nucleosides

“…There have many more studies of other gas phase nucleobase derivatives (for example [3], [4], [14], [24], [25], [26], [27], [28]) which demonstrate that, except for simple methylation, de-excitation rates following UV excitation are generally slower for chemically modified bases and even for some isomers. These observations can, in some cases, be explained by the constraint put on out-of-plane deformations, but more generally modified nucleobases have energy barriers which restrict access to conical intersections.…”

Nonresonant Contribution in Pump–Probe Transient Ion Signal of Adenine

“…100 fs around time zero and suggested a step‐wise deactivation pathway . Later, the excited state lifetime of adenine near the lowest ππ * state (L a ) origin was measured as a function of excitation energy in femtosecond and picosecond time scales.…”

“…The ultrashort excited state lifetime of DNA bases is not an environmental effect but their intrinsic property . The intrinsic excited state dynamics of adenine has been well studied as a model case, along with other bases . Kang et al .…”

New Method for Double-Resonance Spectroscopy in a Cold Quadrupole Ion Trap and Its Application to UV–UV Hole-Burning Spectroscopy of Protonated Adenine Dimer

“…24 Ultrafast excited state dynamics of DNA bases and their subsequent photostability were studied by many groups. [25][26][27][28][29][30][31] Building on the recently reported spectroscopy of protonated DNA bases by Berdakin et al, 32 we report UV-UV hole-burning spectroscopy of Ade2H + using the new method.…”