Transition Energies and Absorption Oscillator Strengths for ${c_4}^{\prime 1}{{\Sigma }_u}^{+}-X^1{{\Sigma }_g}^{+}$, $b^{\prime 1}{{\Sigma }_u}^{+}-X^1{{\Sigma }_g}^{+}$, and ${c_5}^{\prime 1}{{\Sigma }_u}^{+}-X^1{{\Sigma }_g}^{+}$ Band Systems in N₂

Theoretical transition energies and absorption oscillator strengths for the ${c_4}^{\prime 1}{{\Sigma }_u}^{+}$ (v′ = 0–2, 5, 7, 8) − $X^1{{\Sigma }_g}^{+}(v^{\prime \prime }=0\text{--}14)$ and ${c_5}^{\prime 1}{{\Sigma }_u}^{+}$ (v′ = 0, 2) − $X^1{{\Sigma }_g}^{+}$ (v″ = 0–14) Rydberg bands, and $b^{\prime 1}{{\Sigma }_u}^{+}$ (v′ = 0–9, 11, 12, 14–19, 21, 22) − $X^1{{\Sigma }_g}^{+}$ (v″ = 0–14) valence bands of molecular nitrogen are reported. The strong interaction between ${}^1{{\Sigma }_u}^{+}$ states has been dealt with through a vibronic interaction matrix. As a consequence of the Rydberg-valence interaction, irregularities in the vibrational structure of the above band systems are observed. Good agreement is found with the scarce high-resolution data that are available for oscillator strengths. The new band oscillator strengths reported here may be useful for a reliable interpretation of the spectra from atmospheres of the Earth, Titan, and Triton, where $N_2$ is the mayor constituent.