Volume 163, 2013

Time-resolved photoelectron imaging of the iodide–thymine and iodide–uracil binary cluster systems

Abstract

The energetics and dynamics of thymine and uracil transient negative ions were examined using femtosecond time-resolved photoelectron imaging. The vertical detachment energies (VDEs) of these systems were found to be 4.05 eV and 4.11 eV for iodide–thymine (I·T) and iodide–uracil (I·U) clusters, respectively. An ultraviolet pump pulse was used to promote intracluster charge transfer from iodide to the nucleobase. Subsequent electron detachment using an infrared probe pulse monitored the dynamics of the resulting transient negative ion. Photoelectron spectra reveal two primary features: a near-zero electron kinetic energy signal attributed to autodetachment and a transient feature representing photodetachment from the excited anion state. The transient state exhibits biexponential decay in both thymine and uracil complexes with short and long decay time constants ranging from 150–600 fs and 1–50 ps, respectively, depending on the excitation energy. However, both time constants are systematically shorter for I·T. Vibrational autodetachment and iodine loss are identified as the primary decay mechanisms of the transient negative ions of thymine and uracil.

Article information

Article type
Paper
Submitted
22 Dec 2012
Accepted
15 Feb 2013
First published
26 Feb 2013

Faraday Discuss., 2013,163, 59-72

Time-resolved photoelectron imaging of the iodide–thymine and iodide–uracil binary cluster systems

S. B. King, M. A. Yandell and D. M. Neumark, Faraday Discuss., 2013, 163, 59 DOI: 10.1039/C3FD20158A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements