Inelastic Collisions Between Excited Alkali Atoms and Molecules X. Temperature Dependence of Cross Sections for ²P_1/2↔²P_3/2 Mixing in Cesium, Induced in Collisions with Deuterated Hydrogens, Ethanes, and Propanes

Abstract

The dependence on temperature of the cross sections for 2P1/2 ↔ 2P3/2 mixing in cesium, induced in collisions with various deuterated hydrogen, ethane and propane molecules, has been studied in the range 290–650 K. In the cases of hydrogen and ethane, the behavior of the cross sections was found to depend on the degree of deuteration of the molecules. The very large sizes of the mixing cross sections and the isotope effect observed in their variation with temperature, are ascribed to the phenomenon of electronic to rotational energy transfer.

Temperature dependence of cross sections for 72P1/2 ↔ 72P3/2 excitation transfer and for quenching in cesium, induced in collisions with H2, N2, CH4, and CD4

“…for collisions of cesium atoms with N2, Hz, CH,, and CD,. The various cross sections exhibit a variation with temperature, which is about as extensive as in the case of the cesium resonance doublet (2,13). Their values exceed by some two orders of magnitude the corresponding cross sections for collisions with noble gas atoms except for helium (3,14), and are comparable with cross sections reported by Rocchiccioli (15) for transfers from C S~~P~,~ to 8?P31?, 72D312, and 72D512 induced in collisions with N2 and H2, bearing in mind differences in the energy defect AE.…”

“…Equation [13] was then used to calculate the cross sections for CD,. The results are plotted in Fig.…”

Transfer between the cesium62P1/2and62Pitz1, Fox2, Perram3 2011Phys. Rev. A411100View full textAdd to dashboardCite

“…Only electronic to translational energy exchange is available with cesiumrare-gas collisions [2]. The temperature dependence of the cesium-rare-gas energy transfer is not observed in the complex molecules of Walentynowicz, suggesting that the molecules may transfer the energy by rovibrational pathways [7,8].…”

“…Since the 1960s, collision-induced mixing between the 2 P 1/2,3/2 states of alkalis have been thoroughly studied [1][2][3][4][5][6][7][8][9]. These mixing rates have again become of keen interest because of their role in diode-pumped alkali-metal lasers (DPAL).…”

“…The most recent study of the mixing rate between the cesium 6 2 P 1/2 ↔ 6 2 P 3/2 states was performed in 1974 by Walentynowicz [7,8]. In that investigation, a cesium discharge lamp was used to excite the desired states in cesium with a pair of photomultiplier tubes to monitor the fluorescence of the two mixing states.…”