EinsteinA-coefficients and transition dipole moments for some ion-pair to valence transitions in I₂

Amplified spontaneous emission and collisional transfer from the fg+(P3) ion-pair state of I2

“…The errors in I ik and ik ͑R e ͒ for the weak emissions are estimated to be ϳ Ϯ 20% and Ϯ10%, respectively. The I ik values for f0 g + ͑ 3 P 0 ͒ → A1 u ͑aa͒ and f0 g + ͑ 3 P 0 ͒ → C1 u ͑aa͒ are approximately one third of those reported previously 23 for these weak transitions and replace those erroneous values.…”

“…23 However, this value is an upper limit as it has been subsequently shown 10 that there is some D0 u + ͑ 3 P 2 ͒ → 0 g + ͑bb͒ emission, for which the transition dipole is unknown, that was not included in the original calculation. If a value for the …”

TheD′ ↔ A′Transition in ClF

“…It is now clear that under such conditions, the strongest emission belongs to the transition designated as DЈ (2 ( g) 3 P 2 ) 3 AЈ (2 (u) 3 ⌸), 2 in which the terminus is the lowest excited valence state and the origin is (with the exception of ICl (9)) the lowest ion-pair state. This transition owes its intensity in part to the fact that the excitation energy pools in the DЈ state via collision-induced vibrational and rotational relaxation, occurring on a time scale that is short with respect to the radiative decay of the state, which itself is fast (Ͻ10 Ϫ8 s lifetime) (10). These properties made these systems look promising as operating media for electronic transition lasers; in fact, lasing was demonstrated long ago on this transition in all four homonuclear halogens, and in ClF, BrF, and IF (11,12).…”

Efficient long-range collisional energy transfer between the E g+(3P2) and D u+(3P2) ion-pair states of I2, induced by H2O, observed using high-resolution Fourier transform emission spectroscopy

“…9(b), the R:Q:P branch ratios are 1:2:1 as expected. Here, the transition dipole between the minor electronic component in the upper state to the major component in the lower state, β1 g ( 3 P 2 ) → C1 u , is ≈0, 13 hence no interference results. It is also possible that the lower state is subject touncoupling.…”

“…(3) with B = 0.02 cm −1 , J = 110, and v E , v β = 0.1 gives α(8,v β −1) = 3.9 × 10 −2 and α(8,v β ) = 6.3 × 10 −2 . Since the relative intensities of the E0 g + ( 3 P 2 ) → A1 u and β1 g ( 3 P 2 ) → A1 u systems is ≈10 −2 :1, 13 the two transition amplitudes from the mixed upper state have comparable strength and appreciable interference results.…”