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Intermolecular potential energy surface and spectra of He-HCl with generalization to other rare gas-hydrogen halide complexes Generation of soft x rays using a rare gashydrogen plasma focus and its application to xray lithography Appl. Phys. Lett. 48, 686 (1986); 10.1063/1.96743 Summary Abstract: Impact collision ion scattering spectroscopy using noble gas and alkali ions for surface structure analysis J. Vac. Sci. Technol. A 3, 1514(1985; 10.1116/1.573163 Summary Abstract: Hydrogen plasma etching of semiconductors and their oxides

Visible chemiluminescence in the spectral region 5500–7300 Å due to the Ba+N2O and Ba+O3 reactions is observed in argon matrices at temperatures below 15 K. Emission is recorded both as thermoluminescence and during deposition. Two molecular progressions of BaO, with ν00=17 035 and 17 195 cm−1, and ω″e=657 and 651 cm−1, are found and are tentatively attributed to emission in the ã 3Σ+→X̃ 1Σ+ transition for BaO* in different matrix sites, though the Ã 1Σ+→X̃ 1Σ+ transition could also be involved. The presumed excitation mechanism is the reactive population of one or both of the singlet states Ã Σ+1 and/or Ã′ 1Π followed by rapid intersystem crossing to the ã 3Σ+ state. This is the first observation of a chemiluminescent atom transfer reaction in low temperature matrices. Emission due to Ba atoms in the (6s6p1P) →(6s2 1S) transition is also observed, apparently excited by energy transfer from BaO*, most probably from the Ã′ 1Π state.

Stimulated vibration–rotation emission by HF has been observed from states with high rotational excitation following flash photolysis of ClFx–H2–Ar mixtures (ClF, ClF3, ClF5). We report here only those observations connected with the very high rotational states J′?9 (e.g., up to v=1, J=20 and v=2, J=15) which are found to emit under grating-selective conditions. The patterns of emission indicate that direct population of the high J states by the vibrational pumping reaction(s) can be ruled out. Neither is the behavior consistent with Boltzman equilibration. The late threshold times and extended durations point to an energy transfer mechanism that involves rapid V→R deactivation with large ΔJ coupled with V→V up pumping in HF‡–HF‡ collisions to give a cumulative increase in rotational energy. Thus, V→V and V→R processes divert vibrational excitation into rotational excitation where it will tend to ’’pool’’ in high J states for which rotational equilibration is a slow process. These high J, P branch laser emissions reflect the role of rotational degrees of freedom in reaction dynamics and they furnish distinctive clues to energy processes that can influence significantly the efficiency and spectral composition of chemical laser emission.