Far-wing collisional redistribution of light in the barium-rare gas systems

Abstract

We have measured intensity and polarization of far-wing collisionally redistributed light from Ba perturbed by He, Ne, and Kr in a heated cell (T&800 K). Collisional alignment decay rates were also determined. The light was detuned $3!900 cm\ from the 5535 A s BaI 6S!6P resonance line. The rare gas pressure was about 5 mbar. Together with the earlier data of Alford et al. [24], the results form a complete set of data for comparison with forthcoming predictions based on stateof-the-art theory for potential curves of Ba-rare gas systems. With emphasis on systematical trends, the results are discussed in terms of earlier theoretical and experimental findings for similar two-electron systems.

Calculation of ground- and excited-state potential energy curves for barium-rare gas complexes in a pseudopotential approach

“…5, where it is multiplied by Dx 2 to better display the pro®le structure. For comparison with experiment we have also plotted the available experimental data reported by Ni et al [10] and Maeyama et al [27]. The calculated pro®le is adjusted to only one experimental point positioned on the blue side of the line centre.…”

“…For the alkaline earth atoms, the majority of experiments has been done for Ca, Sr and Ba. In particular, for the barium atom, pressure-broadening eects were measured, among others, by Kielkopf [1], Harima et al [2], Ehrlacher and Huennekens [3,4] and Kanorsky et al [5], spin-changing collisions were studied by Breckenridge and Merrow [6] and Visticot et al [7] and polarization eects were investigated by Alford et al [8], Visticot et al [9] and Ni et al [10]. Excitation transfer among low-lying excited states of the Ba atom induced by collisions with rare gas (RG) atoms were studied by Ehrlacher and Huennekens [11], Vadla et al [12] and Brust and Gallagher [13].…”

“…(10) for Ba-Ne: d thermally averaged values for 800 K; h experimental values[10]; , experimental values[27] …”

One and Two-Electron Investigation of Electronic Structure for Ba+Xe and BaXe van der Waals Molecules in a Pseudopotential Approach

“…According to our knowledge, the first experience measuring the pressure broadening effects was performed by Kielkoft; 14 thereafter, absorption coefficients and interatomic potentials were determined by Harima et al 15 Breckenridge and Merrow 16 have studied spin-changing collisions with rare gas atoms. Excitation transfer among excited states of Ba induced by collision with rare gas was investigated by Ehrlacher and Huennekens 17 and also by Valda et al 18 Intensity and polarization of far-wing collisionally redistributed light from Ba atom perturbed by rare gas and collisional alignment decay rates were studied by Andersen et al 19 Diffusion of the ground and lowest 3 D j metastable state barium atoms in a buffer gas was determined by Namiotka et al 20 Despite the diverse experiences concentrated on studying the Ba-RG complexes, the calculation of appropriate collisional processes is scarce, possibly because these studies require the knowledge of reliable potential energy curves which remain poorly known for Ba-RG systems. These complexes have been studied for the first time by Czuchaj et al 21 using ab initio calculation.…”

Computational study of the electronic structure of the Srm+Kr (m = 0, 1) van der Waals complexes

“…Actually, the PESs determined by the theoretical quantum method can be used to study the optical collision processes [4,5]. In addition, the AE-RG systems can serve to understand the chemical and physical phenomena such as energy transfer, laser media, metal-ligand interaction, and collision cross-sections for such electrical discharges [6][7][8][9]. Moreover, these Van der Waals clusters can explain the solvation process [4].…”