Kinetic study of energy transfer from He(n=2,3) to Ne, Ar, Kr, and Xe

Abstract

Time-resolved spectroscopic studies have been carried out on various emissions from He-Ar, He-Kr, He-Xe, and He-Ne mixtures to obtain kinetic information and quenching cross sections following charged-particle excitation. Our results are consistent with the pathways model of Payne, Klots, and Hurst in which Jesse effects are due primarily to energy transfer from $\mathrm{He}\left(2\mathrm{}{}_{}{}^1{}_{}{}^{}S\right)$ to an atom or molecule which is consequentially ionized. Quenching cross sections for $\mathrm{He}\left(2\mathrm{}{}_{}{}^1{}_{}{}^{}S\right)$)-Ar, -Kr, and -Xe at thermal (300°K) collision energy were obtained as 22.5, 42, and 70 ${\mathrm{\AA }}^2$, respectively, with an accuracy of 10%. These results are smaller than theoretical calculations which make use of the orbiting approximation, but agree well with experimental data obtained by crossed-molecular-beam methods. Using the same method, we obtained for the first time room-temperature quenching cross sections for $\mathrm{He}\left(2\mathrm{}{}_{}{}^1{}_{}{}^{}P\right)$)-Ar and $\mathrm{He}\left(3\mathrm{}{}_{}{}^1{}_{}{}^{}P\right)$)-Ne, -Ar, -Kr, -Xe (142 ± 42, 42 ± 4, 53 ± 5, 39 ± 4, and 73 ± 7 ${\mathrm{\AA }}^2$, respectively). These results are larger than theoretical calculations based on the dipoledipole mechanism by Katsuura and Watanabe. Quenching cross sections for $\mathrm{He}\left(3\mathrm{}{}_{}{}^3{}_{}{}^{}P\right)$)-Ne, -Ar, -Kr, -Xe, and $\mathrm{He}\left(3\mathrm{}{}_{}{}^1{}_{}{}^{}D\right)$)-Ne were obtained as 32 ± 5, 22 ± 3, 17 ± 3, 67 ± 10, and 30 ± 5 ${\mathrm{\AA }}^2$, respectively.