- Conference date: 18-22 November 1985
- Location: Dallas, TX, USA
Photochemical isomerization provides a practical testing ground for activated barrier crossing theories. Stilbene is a prototype, because (1) reaction may be initiated by a short optical pulse and the decay of the excited trans isomer followed optically, and (2) the isomerization rate is slow compared to vibrational or solvent relaxation processes in solution. The goal is to understand the effects of the medium upon the reaction kinetics proceeding from the isolated molecule to the low and the high pressure gas, and liquid solution. Towards this end time correlated single photon counting experiments of stilbene isomerization are discussed from isolated molecule conditions up to 90 atm of methane gas. In statistical theories of barrier crossing the transition state rate at temperature T, k TST (T), represents an upper limit for the reaction rate. However, contrary to expectation, for pressures greater than about 2 atm the isomerization rate was found to exceed k TST (T) by over a factor of 2 at 5 atm, and by as much as 10 times at 90 atm. Connections between the various types of experimentally observed rates will be discussed, taking into account their different statistical properties.
- Photochemical reactions
- Transition state theory
- Chemical reaction theory
- Collision induced chemical reactions
Daniel Baumann, Mark G. Jackson, Peter Adshead, Alexandre Amblard, Amjad Ashoorioon, Nicola Bartolo, Rachel Bean, Maria Beltrán, Francesco de Bernardis, Simeon Bird, Xingang Chen, Daniel J. H. Chung, Loris Colombo, Asantha Cooray, Paolo Creminelli, Scott Dodelson, Joanna Dunkley, Cora Dvorkin, Richard Easther, Fabio Finelli, Raphael Flauger, Mark P. Hertzberg, Katherine Jones‐Smith, Shamit Kachru, Kenji Kadota, Justin Khoury, William H. Kinney, Eiichiro Komatsu, Lawrence M. Krauss, Julien Lesgourgues, Andrew Liddle, Michele Liguori, Eugene Lim, Andrei Linde, Sabino Matarrese, Harsh Mathur, Liam McAllister, Alessandro Melchiorri, Alberto Nicolis, Luca Pagano, Hiranya V. Peiris, Marco Peloso, Levon Pogosian, Elena Pierpaoli, Antonio Riotto, Uroš Seljak, Leonardo Senatore, Sarah Shandera, Eva Silverstein, Tristan Smith, Pascal Vaudrevange, Licia Verde, Ben Wandelt, David Wands, Scott Watson, Mark Wyman, Amit Yadav, Wessel Valkenburg and Matias Zaldarriaga
Data & Media loading...
Article metrics loading...