High-Resolution Experimental Study on Photodissocaition of N2O

Abstract

We study the photodissociation dynamics of nitrous oxide using the time-sliced ion velocity imaging technique at three photolysis wavelengths of 134.20, 135.30, and 136.43 nm. The O(1SJ=0)+N2(X1∑+g) product channels were investigated by measuring images of the O(1SJ=0) products. Vibrational states of N2(X1∑+g products were fully resolved in the images. Product total kinetic energy releases (TKER) and the branching ratios of vibrational states of N2 products were determined. It is found that the most populated vibrational states of N2 products are v=2 and v=3. The angular anisotropy parameters (β values) were also derived. The β values are very close to 2 at low vibrational states of the correlated N2(X1∑+g products at all three photolysis wavelengths, and gradually decrease to about 1.4 at v=7. This indicates the dissociation is mainly through a parallel transition state to form products at lower vibrational states, and the highly vibrational exited products are from a more bent configuration. This is consistent with the observed shift of the most intense rotational structure in the TKER as the vibrational quantum number increases.