Two-photon dissociation dynamics of N2O: The N(2P <i>J</i> ) and N(2D <i>J</i> ) atom channels

Two-photon dissociation dynamics of N2O were investigated by means of the time-sliced velocity map ion imaging technique. The N(2PJ) + NO(X2Π) and N(2DJ) + NO(X2Π) channels were accessed via two-photon excitation in the wavelength range of 218-236 nm. The four lobes in the angular distributions were clearly observed in both N-atom product channels, implying that the coherence between the two sequential transitions in the overall two-photon photodissociation process at the energies investigated has a significant influence on the angular distribution of the products. In addition, the translational energy distributions have been determined from the recorded images, revealing highly inverted vibrational populations of both NO products. In the N(2PJ) channel, initial vibrational excitation has a significant impact on the photodissociation dynamics of N2O via 3pσ1Π states. According to experimental results, the N(2PJ) channel may proceed via a bent configuration dissociation pathway involving coupling to an A' symmetry potential energy surface that has not yet been theoretically reported. While the N(2DJ) channel may be preferentially formed via triplet and singlet Rydberg states that couple to the 43A' and 51A' states, followed by dissociation in a bent geometry.