Abstract
Oscillator strengths of 23 electric-dipole-allowed bands of 14N2 in the 86.0-89.7 nm (111 480-116 280 cm-1) region are reported from synchrotron-based photoabsorption measurements at an instrumental resolution of 6.5× 10-4 nm (0.7 cm-1) full width at half maximum. The absorption spectrum comprises transitions to vibrational levels of the cn1Πu (n=3,4), o31Πu, and c′n+1 σu+(n=3,4) Rydberg states as well as the b 1Πu and b′1σu + valence states. The J dependences of band f -values derived from the experimental line f -values are reported as polynomials in J (J+1) and are extrapolated to zero nuclear rotation in order to facilitate comparisons with the results of coupled Schrödinger equation calculations. Many bands in this study are characterized by a strong J dependence of the band f -values and display anomalous P -, Q -, and R -branch intensity patterns. Predissociation line widths are reported for six bands. The experimental f -value and line-width patterns inform current efforts to develop comprehensive spectroscopic models for N2 that incorporate rotational effects and predissociation mechanisms, and are critical for the construction of realistic atmospheric radiative-transfer models.
Original language | English |
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Article number | 194308 |
Journal | Journal of Chemical Physics |
Volume | 131 |
Issue number | 19 |
DOIs | |
Publication status | Published - 2009 |