Volume 157, 2012

Three-state surface hopping calculations of acetaldehyde photodissociation to CH3 + HCO on ab initio potential surfaces

Abstract

We report Trajectory Surface Hopping (TSH) calculations of CH3CHO photodissociation involving three electronic states, S1, T1, and S0, with a focus on the radical products CH3 + HCO, which can be formed from both T1 and S0. We use previously reported potential energy surfaces and spin–orbit couplings for T1 and S0 and report a new potential and spin–orbit coupling for S1 here. Roughly 32 000 trajectories are performed at energies corresponding to seven photolysis wavelengths between 372 and 230 nm. Motivated by recent experiments, we examine the branching ratio of the T1 to S0 pathways as a function of photolysis energy. We also present the relative translational energy and CH3 vibrational energy distributions from these pathways at a photolysis energy of 100 kcal mol−1, formed from both the T1 and S0 potentials. As with standard quasiclassical trajectory calculations, violation of zero-point energy for products also occurs in TSH calculations. This is shown to be a serious issue for this branching ratio and one of several methods considered to deal with this issue is shown to give satisfactory results.

Article information

Article type
Paper
Submitted
24 Jan 2012
Accepted
29 Feb 2012
First published
29 Feb 2012

Faraday Discuss., 2012,157, 27-39

Three-state surface hopping calculations of acetaldehyde photodissociation to CH3 + HCO on ab initio potential surfaces

B. Fu, Y. Han and J. M. Bowman, Faraday Discuss., 2012, 157, 27 DOI: 10.1039/C2FD20010D

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