Study of the ArBr−, ArI−, and KrI− anions and the corresponding neutral van der Waals complexes by anion zero electron kinetic energy spectroscopy

Abstract

Three rare gas halide (RgX−) anions, ArBr−, ArI−, and KrI−, and the corresponding open-shell van der Waals complexes, ArBr, ArI, and KrI, were studied with anion zero electron kinetic energy (ZEKE) spectroscopy. Photodetachment of each anion accesses the three lowest-lying electronic states (the X1/2, I3/2, and II1/2 states) of the neutral complex. The spectra for each system reveal well-resolved progressions in the low frequency vibrations of the anion and the three neutral electronic states, providing a detailed spectroscopic probe of the Rg⋅X− and Rg⋅X interaction potentials. The line shapes observed in the ZEKE spectra are analyzed in terms of the line strengths of the underlying rotational transitions. From our data, we construct the potential energy curve for each neutral state as well as for the anion, and these interaction potentials are compared to potentials obtained from scattering and ion mobility experiments.

Coupled cluster study of structural properties of RgI and RgI− (Rg = He, Ne, Ar) weakly bound molecules

“…The calculated equilibrium bond length at CCSD(T)/BS3 level is little lower than the experimental value of Zhao et al, but the dissociation energy and rotational constant agree well with the experimental values. It may be noted that the equilibrium bond length obtained at CCSD(T)/BS2 level is very close to the experimental value [1]. The equilibrium bond length calculated by Buchachenko et al [8] is higher than that of ours.…”

“…ground state are displayed in Table 3 along with other theoretical and experimental values. It can be noted that the experimental equilibrium bond length quoted by Batsanov et al is higher than that reported by Zhao et al [1]. The calculated equilibrium bond length at CCSD(T)/BS3 level is little lower than the experimental value of Zhao et al, but the dissociation energy and rotational constant agree well with the experimental values.…”

“…The RgX -potentials are very useful in determining the diffusion and the mobility of ions in plasma and discharges. The only experimental work on RgX and RgXanions was carried out by Neumark et al [1] using zero electron kinetic energy (ZEKE) spectroscopy. They studied potential parameters of the neutral and anions systems.…”

Negative ions, mass selection, and photoelectrons

“…Because the P 3/2 component of iodine is degenerate (in contrast to P 1/2 ), it is reasonable to explain this structure by the lifting of this degeneracy. This effect has been found for most of the iodine-containing van der Waals clusters studied so far [e.g., ArI, KrI (Zhao et al, 1994), I(CO 2 ) (Zhao et al, 1993)] by high-resolution anion ZEKE. The observed energy splitting is between 30 -300 cm…”

Study of KrO− and KrO via Slow Photoelectron Velocity-Map Imaging Spectroscopy and ab Initio Calculations

“…Neither scaling the depth of ab initio interaction potentials and shifting of their equilibrium distances, nor replacing the neutral potentials by the empirical scattering potentials from ref 18 improves the situation noticeably. Likewise, rotationally resolved simulations that used rotational line strength factors 3,20 failed to produce better agreement with the measurements in the region above 13000 cm -1 . These efforts suggest that the discrepancies between the measured and simulated spectra mostly originate from the photodetachment transition probability calculations.…”