Spectroscopic studies of diatomic noble gas halides. IV. Vibrational and rotational constants for the X, B, and D states of XeF

Abstract

The B→X and D→X systems of XeF are recorded by photographing the emission from the low-pressure Xe*/XeF2 and Ar*/XeF2 reactions. A rotational analysis is obtained for the 1–2 band of B–X, for which isotopic blending is negligible. Vibrational parameters for the X, B, and D states are derived from a direct, weighted least-squares fit of all assignments for both transitions. Rotational parameters are deduced from the vibrational dependence of the band shapes and intensities. Some significant results of this analysis are ReX=2.293 å, ReB=2.631 å, ReD=2.51 Å, ωeX=225 cm−1, ωeB=309.0 cm−1, ωeD=350.1 cm−1, and 𝒟eX=1175 cm−1. The Franck–Condon factors for many of the bands in both systems show a strong rotational dependence, which is to be expected in transitions of this type, for reasons discussed herein.

The B(1/2 2P3/2)→X(1/2 2Σ+) transition in XeBr

“…Indeed, the only exceptions to this picture appeared to be the B→X and D( 1 2 2 P 1/2 )→X transitions in XeCl, where fine violetdegraded band structure was observed, 5,18 and these same transitions in XeF, where quite rich discrete structure was manifested. [19][20][21][22][23] For XeBr ͑and most other RgX species͒ the high-pressure B→X spectrum seemed to show only soft undulatory structure, with intervals roughly marking the vibrational spacing in the excited state ͑Fig. 1͒.…”

Generation of tunable short pulse VUV radiation by four-wave mixing in xenon with femtosecond KrF-excimer laser pulses

“…8(b)]. Considering potential curves [21] and Franck-Condon factors [22], this line can be attributed to a XeF ( B , U' = 2) -, XeF ( X , U'' = 5) transition.…”

Chemiluminescence of argon bromide. II. Potential curves of ArBr and population distributions in the B (1/2) and C (3/2) electronic states

“…(15)). To a very good approximation, such changes always altered the slopes of the inner and outer limbs of the potential in the same sense and could be parametrized by changes in the vibration frequency, we' A reasonable range, we = 200 ± 10 cm -I, by analogy with w e (KBr)=218 cm-I , leads to a 10% uncertainty in the slopes of V' and thus of V" at r< re and a smaller uncertainty at larger r.…”

“…Therefore, a representative potential V~ of the Rittner type, 10 15) (where D; is the bond energy relative to the atomic ions so that the energy zero corresponds to the minimum of the potential) was developed for the emitting B(t) state. For the present calculations, the polarizability of Ar+ was taken to be equal to that of K+, 10 while the repulsive terms were chosen to give physically reasonable values for the dissociation energy, the vibration frequency, w~, and the bond length, r:.…”