Srinivasan S. Iyengar Department of Chemistry, Indiana University Effect of water on structure, reactivity and vibrational properties of fundamental ions: Insights from ab initio molecular dynamics

Can a 5-coordinated pentavalent oxygen be detected using vibrational action spectroscopy? Four and five coordinated oxygens are stable in hydroxide water clusters The spectroscopic features seem to differ in cm -1

But, finite temperature ab initio dynamics does allow them to interconvert!! 200K: Internal temperature The “Eigen” and Zundel forms for hydroxide?

Dynamics affects spectroscopy  Temperature dependence of the spectrum  Indicates it may be possible to probe experimentally through single-photon and multi-photon experiments The isomers are spectroscopically distinct

A protonated system seems to be less susceptible to cluster temperature The protonated species is a combination of Zundel and Eigen

These results should have an important bearing on the reactivity of these species, which is currently under investigation.