Electronic spectra of ArXe molecules in the region of Xe* (6s′, 6p, 5d), 77 000–80 200 cm⁻¹, using resonantly enhanced multiphoton ionization

Abstract

The excited electronic states of ArXe molecules in the region 77 000–80 200 cm−1 were studied using the (2+1) and (3+1) resonance-enhanced multiphoton ionization methods. The use of different methods of multi-photon excitation and Ar+ ion registration allowed us to obtain some new data. Molecular constants were obtained for previously unknown excited states of molecules with the following dissociation limits: ArXe* → Ar1S0+Xe*6р[5/2]3 with Ω = 2, 3 symmetry; Ar1S0+Xe*6p[3/2]2 with Ω = 1, 2 symmetry; Xe0S1 → Xe*6s′[1/2]01 with Ω = 0+ symmetry.

Structure and dynamics of the electronically excited C 1 and D 0+ states of ArXe from high-resolution vacuum ultraviolet spectra

“…The present article focuses on an investigation of the spectrum of ArXe in the vicinity of the Ar( 1 S 0 ) + Xe* (Xe* = 6s [1/2] o 1 and 6p[1/2] 1 ) dissociation limits in the spectral region 77100-77250 cm −1 by high-resolution VUV spectroscopy. In this spectral region two band systems, labelled C 1 ← X and D 0 + ← X in previous studies, overlap spectrally 9,28,29,32,36,38 and reveal pronounced perturbations and a rich predissociation dynamics. The high resolution achieved in our investigation enabled us to (i) precisely measure isotopic shifts and determine unambiguous vibrational assignments, (ii) fully resolve the rotational structure of most vibrational bands and obtain information on the potentialenergy functions of the excited states and on perturbations, (iii) observe the hyperfine structure of the spectra of Ar 129 Xe and Ar 131 Xe and thus gain additional insight into the electronic structure, and (iv) derive an upper bound for the predissociation rates from the observed linewidths.…”

“…We therefore suspect that the very weak feature observed at 77069.3 cm −1 in Ref. 28 (but not observed in later studies 29,32,36,38 ) and assigned to the C-X (0,0) transition is not part of the C-X band system.…”

“…As will be shown in Secs. III C and III D, the analysis of the hyperfine structure of the 40 Ar 129 Xe and 40 Ar 131 Xe isotopomers suggests that the diabatic dissociation asymptote of the C 1 state corresponds to Ar( 1 S 0 ) and Xe(6p[1/2] 1 ) fragments, which lies 84.104 cm −1 above the dissociation limit of the D 0 + state, and not to Ar( 1 S 0 ) and Xe(6s [1/2] o 1 ) as was assumed by Liu et al 29 In their recent study of the C 1 state by (2 + 1) and (3 + 1) multiphoton excitation, Khodorkovskiȋ et al 38 reached a similar conclusion, which is also supported by the calculations of Hickman et al 26 The analysis of the rotational structure of the C ← X 0 + transition of 40 Ar 132 Xe was carried out using Eq. (1) in combination with Eq.…”

“…single-photon VUV spectra 9,[28][29][30][31][32] and resonance-enhanced multiphoton ionization spectra. 21,22,[33][34][35][36][37][38] Several electronically excited states located in the vicinity of the Ar( 1 S 0 ) + Xe* (Xe* = 6s [ ) dissociation limits have been assigned from direct observation of the rotational structure (see, e.g., Ref. 29), from the dependence of the observed intensity distributions on the polarization of the radiation used to record multiphoton excitation spectra (see, e.g., Ref.…”

Electronic spectra of ArXe molecules in the region of Xe* (5d, 7s, 7p, 6p′), 80 300–89 500 cm−1, using resonantly enhanced multiphoton ionization

“…In this paper we continue a series of studies of the excited states of rare gas (RgRg ) diatomic molecules using multi-photon resonance laser ionization by time-of-flight mass-spectrometer monitoring of ions [1][2][3][4][5]. In this paper the excited electronic states of ArXe were studied using (2 + n) and (3 + n) REMPI methods in the wide high-energy spectral region of 80 300-89 500 cm −1 .…”