Reactions of Metastable Nitrogen Atoms

Abstract

The line absorption technique was applied to the kinetic study of the two metastable atomic nitrogen states N (22D) and N (22P) in a flowing afterglow system. The optical absorptions of the NI 1493-Å (2p32D−3s2P) and 1743-Å (2p32D−3s2P) transitions were used for the quantitative measurement of N (22D) and N (22P) concentrations. Deactivation of N (2D) and N (2P) by the Pyrex tube wall was found to be very efficient, i.e., occurs at nearly every collision. The second-order rate constants at 300°K for the removal of N (2D) by O2, N2O, CO2, NO, N2, Ar, and He were found to be (6±2)×10−12, (3.5±1.2)×10−12, (5±2)×10−13, (7±2.5)×10−11, (1.6±0.7)×10−14, (1±0.6)×10−16, and ≤ 1.6×10−16 cm3 sec−1, respectively. It was established that the process for the first three reactant gases results in chemical reaction rather than physical quenching.

Critically evaluated rate constants for gaseous reactions of several electronically excited species

“…is chemical in nature is well established (Lin & Kaufman, 1971;Dodge & Heicklen, 1971;Black et al, 1969Black et al, , 1975. The predominant reaction pathway appears to be to ground state products with a small contribution (0.3 %) in the channel producing NO(B2Il) (Slanger et aI., 1971;Herbelin & Cohen, 1973).…”

“…(A 3E+) although the reaction has sufficient exothermicity . The stoichiometry of the reaction was verified by Lin and Kaufman (1971) who monitored the oxygen atoms produced by the subsequent reaction between N and the NO product. The nine measures of k N • o vary by a factor of three.…”

CRITICAL REVIEW OF N, N + , N + 2 , N ++ , And N ++ 2 MAIN PRODUCTION PROCESSES AND REACTIONS OF RELEVANCE TO TITAN'S ATMOSPHERE

“…Umemoto (2007) measured the H atom yield and D atom yield to be equal to 0.52 and 0.33, for the reactions with C 2 H 2 and C 2 D 2 , respectively. They conclude that the presence of an (Herron 1999) N 2 (A 3 Σ + u ) + C 2 H 2 298 1.6 × 10 −10 P-CL N 2 (A 3 Σ + u ) + C 2 H 2 298 1.6 × 10 −10 FP-CL (Callear & Wood 1971) N 2 (A 3 Σ + u ) + C 2 H 2 298 2.5 × 10 −10 DF-CL (Meyer et al 1971) N 2 (A 3 Σ + u ) + C 2 H 2 298 2.0 × 10 −10 DF-LIF (Bohmer & Hack 1991) N 2 (A 3 Σ + u ) + C 2 H 2 298 2.0 × 10 −10 Compilation (Herron 1999) N 2 (A 3 Σ + u ) + C 2 H 2 298 (1.40 ± 0.02) × 10 −10 for C 2 H 2 LP-LIF (Umemoto 2007) (1.45 ± 0.03) × 10 −10 for C 2 D 2 N 2 (A 3 Σ + u ) + C 2 H 4 298 1.2 × 10 −10 FP-CL N 2 (A 3 Σ + u ) + C 2 H 4 298 1.5 × 10 −10 P-CL N 2 (A 3 Σ + u ) + C 2 H 4 298 1.1 × 10 −10 FP-CL (Callear & Wood 1971) N 2 (A 3 Σ + u ) + C 2 H 4 298 1.6 × 10 −10 DF-CL (Meyer et al 1971) N 2 (A 3 Σ + u ) + C 2 H 4 298 0.64 × 10 −10 DF-LIF (Dreyer & Perner 1973) N 2 (A 3 Σ + u ) + C 2 H 4 298 1.2 × 10 −10 DF-ES (Clark & Setser 1980) N 2 (A 3 Σ + u ) + C 2 H 4 298 1.2 × 10 −10 DF-CL (Cao & Setser 1985) N 2 (A 3 Σ + u ) + C 2 H 4 298 1.0 × 10 −10 DF-LIF (Thomas et al 1987 N 2 (A 3 Σ + u ) + C 2 H 6 298 3.6 × 10 −13 FP-CL (Callear & Wood 1971) N 2 (A 3 Σ + u ) + C 2 H 6 298 2 × 10 −14 DF-CL (Meyer et al 1971) N 2 (A 3 Σ + u ) + C 2 H 6 298 2.9 × 10 −13 PR-AS (Dreyer & Perner 1973) N 2 (A 3 Σ + u ) + C 2 H 6 300-370 2.2 × 10 −13 a FP-CL (Slanger et al 1973) N 2 (A 3 Σ + u ) + C 2 H 6 298 2.3 × 10 −13 Compilation (Herron 1999) (Husain et al 1972) N ( 2 D) + N 2 298 1.5 × 10 −14 FP-RA (Husain et al 1974) N ( 2 D) + N 2 298 1.8 × 10 −14 FP-CL ) Sugawara et al 1980) N ( 2 D) + N 2 213-294 2.4 × 10 −14a PR-RA (Suzuki et al 1993b) N ( 2 D) + N 2 298 1.7 × 10 −14 Compilation (Herron 1999) N ( 2 P ) + N 2 400 6 × 10 −14 DF-RA (Lin & Kaufman 1971) N ( 2 P ) + N 2 298 3 × 10 −16 DF-RA (Husain et al 1972) N ( 2 P ) + N 2 298 1.0 × 10 −16 FP-RA (Husain et al 1974)…”

“…Herron has suggested 1.7 × 10 −14 cm 3 s −1 as the recommended room temperature rate constant, which is an average value of the most accurate available data (Husain et al 1974;Lin & Kaufman 1971;Slanger & Black 1976;Sugawara et al 1980;Suzuki et al 1993b) (see Table 3). Such a low value was explained by the inefficiency of crossing between doublet and quartet N 3 potential energy surfaces (Donovan & Husain 1970).…”

Solar influence on the redline dayglow emission under equinox conditions

“…A4 Oð 1 DÞþhn ð557:7 nmÞ A 4 ¼ 1.18 s À 1 Nicolaides et al (1971) Nð 2 DÞþO 2 À! k5 NO þ Oð 1 DÞ k 5 ¼6.0 Â 10 À 12 Lin and Kaufman (1971) N þ þ O 2 À! k6 NO þ þ Oð 1 DÞ k 6 ¼6.0 Â 10 À 10 Langford et al (1986) Nð 2 DÞþOÀ!…”