The quenching of metastable O2(1Δg) and O2(1Σg+) molecules

Becker, K. H.; Groth, W.; Schurath, U.

doi:10.1016/0009-2614(71)85004-2

Cited by 156 publications

(64 citation statements)

References 10 publications

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“…In the last five years a number of laboratories Experimental have reported rate constants for the quenching of 02('C,+) in the gas phase (1)(2)(3)(4)(5)(6). It would appear that in all cases the quenching did not involve chemical reaction, and 02(lC,+) was relaxed to O,('A,) which lies only 15 kcal below it (7,8).…”

mentioning

confidence: 99%

The Quenching of O₂(¹Σ_g⁺) by Aliphatic Hydrocarbons

Davidson¹,

Ogryzlo²

1974

Can. J. Chem.

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Rate constants for the quenching of O2(1Σg+) in the gas phase have been determined for 12 aliphatic hydrocarbons. The values are discussed in terms of a mechanism in which the magnitudes of the rate constants are determined by the abilities of the quenchers to become vibrationally excited when O2(1Σg+)is relaxed to O2(1Δg).The resulting equations are tested quantitatively by relating the rate constants to the absorption spectra of the quenchers at the frequencies of the O2(1Σg+−1Δg) transition.

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mentioning

confidence: 99%

The Quenching of O₂(¹Σ_g⁺) by Aliphatic Hydrocarbons

Davidson¹,

Ogryzlo²

1974

Can. J. Chem.

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“…118 ' 19 ' These results demonstrate that the loss of emission due to quenching is largely offset by the continuous production of 0 2 'A g .…”

Section: Dedicated To Dr Robert Corleymentioning

confidence: 52%

Volume 1: The Solid-Gas Singlet Delta Oxygen Generator

Alfano¹

2004

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Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. REPORT DATE (DD-MM-YYYY) 08-03-2004 REPORT TYPEFinal Technical Report, Vol. 1 (From -To) DATES COVERED SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR'S ACRONYM(S)Air Force Research Laboratory (AFMC) XC AFRL/PRSP SPONSOR/MONITOR'S REPORT10 E. Saturn Blvd. NUMBER(S)Edwards AFB CA 93524-7680 AFRL-PR-ED-TR-2004-0041, Vol. 1 DISTRIBUTION / AVAILABILITY STATEMENTApproved for public release; distribution unlimited. SUPPLEMENTARY NOTESThis report is Volume 1 of 2 volumes. Vol 2 is entitled, "History of the AFRL/USC DARPA Program on Polynitrogen Chemistry." ABSTRACTThe recently completed research program at the Air Force Research Laboratory, Edwards AFB Site, had as its goals for the component dealing with solid-gas generation of singlet delta oxygen: a) construction of a Raman diagnostic system for the simultaneous measurement of excited and ground state oxygen in gas-solid reactions between solid peroxides and hydrogen halides or chlorine gas, b) exploration of alternate singlet delta oxygen sources, and c) technical chemistry support to a parallel engineering effort at Boeing. This technical report summarizes the results which were obtained during this program, and a second volume will cover the results for polynitrogen research. The Appendices 2-4 contain copies of a recently awarded U.S. patent for the chemical generation of singlet delta oxygen, an article in the AFRL Technology Horizons magazine, and a journal article from Angewandte Chemie International Edition, respectively. All of the published work was done under DARPA sponsorship. REACTION CHEMISTRYWe have identified two previously unreported gas-solid reactions which produce 1 ∆O 2 without any external heat, light, or electrical input:Reactions (1) Our investigation of the basic chemistry of these gas-solid reactions was not exhaustive but some generalities have emerged which can be correlated with spectroscopic experiments conducted in parallel. Over thirty material balances were determined by adding weighed amounts of solid sodium peroxide to ampoules contained in a nitrogen atmosphere dry box. The ampoules which were equip...

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“…However, another explanation for the small value of k 2 is that quintet FeO 2 , which forms initially from Fe + O 2 (a), dissociates rapidly to Fe(a 5 F) + O 2 (X). This channel represents nearresonant energy transfer ( E = -10 to +4 kJ mol −1 , depending on the Fe spin-orbit multiplet), and is thus likely to be the major channel of reaction (2). The excited Fe(a 5 F) atoms produced would be quenched 41 Table III.…”

Section: Discussion and Theoretical Analysismentioning

confidence: 99%

“…7 Most recently, satellite-borne spectrometric observations of the earth's dayglow have been used to retrieve the global layer of Mg. 8 Ca, Mg, and Fe atoms all react rapidly with O 3 . 9, 10 However, given the daytime [O 2 …”

Section: Introductionmentioning

confidence: 99%

O2(a1Δg) + Mg, Fe, and Ca: Experimental kinetics and formulation of a weak collision, multiwell master equation with spin-hopping

Plane

Whalley

Francés‐Soriano

et al. 2012

The Journal of Chemical Physics

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The first excited electronic state of molecular oxygen, O 2 (a 1 g ), is formed in the upper atmosphere by the photolysis of O 3 . Its lifetime is over 70 min above 75 km, so that during the day its concentration is about 30 times greater than that of O 3 . In order to explore its potential reactivity with atmospheric constituents produced by meteoric ablation, the reactions of Mg, Fe, and Ca with O 2 (a) were studied in a fast flow tube, where the metal atoms were produced either by thermal evaporation (Ca and Mg) or by pulsed laser ablation of a metal target (Fe), and detected by laser induced fluorescence spectroscopy. O 2 (a) was produced by bubbling a flow of Cl 2 through chilled alkaline H 2 O 2 , and its absolute concentration determined from its optical emission at 1270 nm (O 2 (a 1The following results were obtained at 296The total uncertainty in these rate coefficients, which mostly arises from the systematic uncertainty in the O 2 (a) concentration, is estimated to be ±40%. Mg + O 2 (a) occurs exclusively by association on the singlet surface, producing MgO 2 ( 1 A 1 ), with a pressure dependent rate coefficient. Fe + O 2 (a), on the other hand, shows pressure independent kinetics. FeO + O is produced with a probability of only ∼0.1%. There is no evidence for an association complex, suggesting that this reaction proceeds mostly by nearresonant electronic energy transfer to Fe(a 5 F) + O 2 (X). The reaction of Ca + O 2 (a) occurs in an intermediate regime with two competing pressure dependent channels: (1) a recombination to produce CaO 2 ( 1 A 1 ), and (2) a singlet/triplet non-adiabatic hopping channel leading to CaO + O( 3 P). In order to interpret the Ca + O 2 (a) results, we utilized density functional theory along with multireference and explicitly correlated CCSD(T)-F12 electronic structure calculations to examine the lowest lying singlet and triplet surfaces. In addition to mapping stationary points, we used a genetic algorithm to locate minimum energy crossing points between the two surfaces. Simulations of the Ca + O 2 (a) kinetics were then carried out using a combination of both standard and non-adiabatic Rice-Ramsperger-Kassel-Marcus (RRKM) theory implemented within a weak collision, multiwell master equation model. In terms of atmospheric significance, only in the case of Ca does reaction with O 2 (a) compete with O 3 during the daytime between 85 and 110 km.

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The quenching of metastable O2(1Δg) and O2(1Σg+) molecules

Cited by 156 publications

References 10 publications

The Quenching of O₂(¹Σ_g⁺) by Aliphatic Hydrocarbons

The Quenching of O₂(¹Σ_g⁺) by Aliphatic Hydrocarbons

Volume 1: The Solid-Gas Singlet Delta Oxygen Generator

O2(a1Δg) + Mg, Fe, and Ca: Experimental kinetics and formulation of a weak collision, multiwell master equation with spin-hopping

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The quenching of metastable O2(1Δg) and O2(1Σg+) molecules

Cited by 156 publications

References 10 publications

The Quenching of O2(1Σg+) by Aliphatic Hydrocarbons

The Quenching of O2(1Σg+) by Aliphatic Hydrocarbons

Volume 1: The Solid-Gas Singlet Delta Oxygen Generator

O2(a1Δg) + Mg, Fe, and Ca: Experimental kinetics and formulation of a weak collision, multiwell master equation with spin-hopping

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The Quenching of O₂(¹Σ_g⁺) by Aliphatic Hydrocarbons

The Quenching of O₂(¹Σ_g⁺) by Aliphatic Hydrocarbons