SURPRISING COMPLEXITY OF A SMALL MOLECULE: PHOTOFRAGMENTATION DYNAMICS OF ICN, ICN$\cdot$Ar$_n$ and ICN$\cdot$(CO$_2$)$_n$

Abstract

The photofragmentation dynamics of ICN$^-$ in isolation and in complexes with argon or CO$_2$ are investigated through a combination of experimental and theoretical studies. Experimentally, we probe the excited state dynamics of ICN$^-$ following excitation to the lowest energy state that correlates to I$^-$ + CN products. In the absence of solvating atoms or molecules, most of the excess charge localizes on I$^-$, although $\approx$ 3\% of the products have the charge localized on the CN$^-$. The introduction of a single CO$_2$ or argon atom changes the branching ratio between the three possible product channels (I$^-$ , CN$^-$ or ICN$^-$). Interestingly when one argon atom is introduced roughly 5\% of the products undergo cage recombination to form ICN$^-$, providing an example of single atom caging., 2651 (2012)} When CO$_2$ is introduced, cage recombination is only seen in larger complexes, but a significant fraction of the photoproducts obtained following excitation of ICN$^-\cdot $CO$_2$ have the charge localized on the CN. These results will be discussed and analyzed using potential surfaces evaluated at the MR-SOCISD level of theory., (in press)