Gas-phase reactions of AlO with small molecules

• Published in: Journal of physical chemistry (1952) 1989-11, Vol.93 (24), p.8045-8052
• Main Authors: PARNIS, J. M, MITCHELL, S. A, KANIGAN, T. S, HACKETT, P. A
• Format: Article
• Language: English
• Subjects: 360603 - Materials- Properties; 400000 - Chemistry; 400500 - Photochemistry; ALKANES; ALUMINIUM COMPOUNDS; ALUMINIUM OXIDES; AROMATICS; BENZENE; CARBON COMPOUNDS; CARBON DIOXIDE; CARBON OXIDES; CHALCOGENIDES; Chemistry; DATA; DATA ANALYSIS; DECAY; ELEMENTS; EMISSION SPECTROSCOPY; ETHANE; Exact sciences and technology; EXPERIMENTAL DATA; FLUORESCENCE SPECTROSCOPY; General and physical chemistry; HYDROCARBONS; HYDROGEN; INFORMATION; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; KINETICS; MATERIALS SCIENCE; MEASURING INSTRUMENTS; MEASURING METHODS; METHANE; NONMETALS; NUMERICAL DATA; ORGANIC COMPOUNDS; OXIDES; OXYGEN COMPOUNDS; Photochemistry; Physical chemistry of induced reactions (with radiations, particles and ultrasonics); PRODUCTION; REACTION KINETICS; SPECTROSCOPY
• ISSN: 0022-3654; 1541-5740
• DOI: 10.1021/j100361a017

AlO is produced in the gas phase at 296 K by reaction of Al atoms with N{sub 2}O following Al atom formation by multiphoton dissociation of trimethylaluminum (TMA). Production and decay of Al and AlO are monitored by laser-induced fluorescence. The combination of efficient vibrational relaxation of AlO by N{sub 2}O and low reactivity of AlO with N{sub 2}O at room temperature allows studies of AlO reaction kinetics to be carried out with a range of molecules using N{sub 2}O as a buffer gas. Second-order rate constants at 296 K (cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}) are reported for the reactions of ground-state Al(3{sup 2}P{sub j}) with N{sub 2}O, (1.1 {plus minus} 0.1) {times} 10{sup {minus}11}; ethylene oxide, (1.3 {plus minus} 0.1) {times} 10{sup {minus}10}, and TMA, (1.3 {plus minus} 0.3) {times} 10{sup {minus}10} in Ar buffer gas, and for reactions of ground-state AlO(X{sup 2}{Sigma}{sup +}, v = O) with ethylene oxide, (2.1 {plus minus} 0.5) {times} 10{sup {minus}10}; tetramethylethylene, (1.1 {plus minus} 0.4) {times} 10{sup {minus}11}; and TMA, (3.0 {plus minus} 1.0) {times} 10{sup {minus}10} in N{sub 2}O buffer gas. A third-order rate constant of (4.3 {plus minus} 0.4) {times} 10{sup {minus}32} cm{sup 6} molecule{sup {minus}2} s{sup {minus}1} is reported for the AlO + CO association reaction in N{sub 2}O buffer gas. Reactions of AlO with CO{sub 2} and C{sub 2}H{sub 4} showed buffer gas pressure dependent pseudo-second-order rate constants, indicative of processes involving formation of association complexes. Estimates are made of the upper limits for the rate constants for reaction of AlO with N{sub 2}O, methane, molecular hydrogen, isobutane, benzene, toluene, CF{sub 2}Cl, CF{sub 3}Br, and CCl{sub 4}, for which the reaction rates at 296 K were negligible.