Photodissociation dynamics of N₃⁺

The photodissociation dynamics of N 3 + excited from its (linear) 3 Σ g - /bent 3 A'ground to the first excited singlet and triplet states is investigated. Three dimensional potential energy surfaces for the 1 A', 1 A', and 3 A' electronic states, correlating with the 1 Δ g and 3 Π u states in linear geometry, for N 3 + are constructed using high level electronic structure calculations and represented as reproducing kernels. The reference ab initio energies are calculated at the MRCI+Q/aug-cc-pVTZ level of theory. For following the photodissociation dynamics in the excited states, rotational and vibrational distributions P(v') and P(j') for the N 2 product are determined from vertically excited ground state distributions. Due to the different shapes of the ground state 3 A' PES and the excited states, appreciable angular momentum j' ∼ 60 is generated in the diatomic fragments. The lifetimes in the excited states extend to at least 50 ps. Notably, results from sampling initial conditions from a thermal ensemble and from the Wigner distribution of the ground state wavefunction are comparable.