Lifetime measurements on the [formula omitted], v=0, 1 and 2 states of molecular nitrogen

• Published in: Chemical physics 2001-07, Vol.270 (1), p.215-225
• Main Authors: Ubachs, W., Lang, R., Velchev, I., Tchang-Brillet, W.-Ü.L., Johansson, A., Li, Z.S., Lokhnygin, V., Wahlström, C.-G.
• Format: Article
• Language: English
• ISSN: 0301-0104
• DOI: 10.1016/S0301-0104(01)00378-0

Excited state lifetimes of c 4 ′ 1Σ + u , v=0–2 states of molecular nitrogen have been determined in a laboratory investigation using a picosecond XUV laser in a pump–probe configuration. For c 4 ′ 1Σ + u , v=0 the lifetime is τ=740±50 ps, for the lowest rotational states. For higher rotational states a gradual shift towards τ=495 ps is found in agreement with previous findings that these states are subject to predissociation. For c 4 ′ 1Σ + u , v=1 no J-dependence is found and values for two isotopomers are reported: τ=330 ps for 14 N 2 and τ=240 ps for 14 N 15 N . For c 4 ′ 1Σ + u , v=2 a lifetime for the lowest rotational states ( J=0–3) was derived: τ=675±50 ps; for J=11 a lifetime of τ⩽120 ps is deduced. All values for the lifetimes including the J-dependences are explained in a model based on Rydberg-valence interaction.