Reaction Dynamics of Electronically Excited Calcium Atom. Issue 1 (1992)

• Record Type: Journal Article
• Authors: Verdasco, E.; Menéndez, M.; Garay, M.; Ureña, A. González; D'azy, O. Benoist; Poblete, F. J.; Taïeb, G.
• Is Part Of: Laser chemistry. Volume 12:Issue 1/2(1992)
• Page Start: 123
• Page End: 136
• Publication Date: 1992
• Subjects: Lasers in chemistry -- Periodicals; 542.8
• DOI: 10.1155/LC.12.123
• Languages: English
• ISSNs: 0278-6273

Abstract

Abstract : Absolute values of the total chemiluminescence cross-section for the beam-gas Ca( 3 P, 1 D) + Cl4 C → CaCl(A, B) + Cl3 C and Ca( 3 P, 1 D) + SF6 → CaF(A, B) + SF5 reactions have been measured at low collision energy, E T = 0.15 and 0.14eV, respectively. Both metastable atomic calcium states Ca( 3 P, 1 D) were produced under low voltage dc-discharge conditions. By changing the discharge conditions, different metastable concentrations were produced to measure the state-to-state cross-section for both 3 P and 1 D reactions. The following values for the total chemiluminescence cross-sections were obtained: σ D 1 = 1.77 Å andσ P 3 = 0.25 Å for the Ca( 3 P, 1 D) + Cl4 C → CaCl(A, B) + Cl3 C reaction. σ D 1 = 0.59 Å 2 andσ P 3 = 0.56 Å 2 for the Ca( 3 P, 1 D) + SF6 → CaF(A) + SF5 reaction. σ D 1 = 0.04 Å 2 andσ P 3 = 0.12 Å for the Ca( 3 P, 1 D) + SF6 → CaF(B) + SF5 reaction. In addition, beam-beam experiments were carried out at the same average low collision energy that of the beam-gas, and therefore, normalization between both experiments was possible. This procedure allowed us to obtain the excitation function of the Ca( 1 D) + SF6 reaction in absolute values over the 0.15–0.60eV collision energy range. On the other hand, by simulation, the ratio of CaCl(B-X/A-X) emissions intensities was found to be of 0.15. The variation of this ratio with the relative concentration of 1 D/ 3 P in a Broida oven leads to the conclusion that this state favours the formation of the B state in the chemiluminescent Ca( 3 P, 1 D) + CH3 CHCl2 → CaCl(A, B) + CH3 CHCl reaction.