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Abstract

The reaction between NO-3 and CH-20 was studied in a 450-L glass/Teflon chamber by using FT-IR spectroscopy as the analytical technique. NO-3 was obtained in equilibrium with N-20-5 introduced from evaporation of the solid phase into the cell or generated in the cell itself by reacting NO-2 with O-3. Experiments were performed in both cases at 295 pm 2 K and 740 Torr in purified air. "13"CH-20 was used to avoid spurious effects on the measured CO; "13"C"18"0 was introduced to estimate the OH radical concentration in the system from the buildup of the oxidation product "16"0"13"C"18"0. "13"CH-20, "13"C"16"0, N-20-5, O-3, NO-2 and H"13"COOH time-dependent concentrations were measured and the data fitted on the basis of a model involving 31 reactions, with the aid of the FACSIMILE computer program. A rate constant for the reaction NO-3 + CH-20 equal to (5.4 pm 1.1) times 10"-16" cm3 molecule"-1" s"-1", at 295 pm 2 K and 740 Torr, has been obtained assuming for the reactions N-20-5"+"rm M"atoprightleftharpoons" NO-3 + NO-2 an equilibrium constant equal to 5.3 times 10"10" molecules cm"-3". Significant differences have been found between the measured concentrations of OH and HCOOH with respect to those predicted by the model. In the framework of this study, the absolute strength of the nu-6 bank of H"12"COOH (1045-1150 cm"-1") has been measured equal to (3.48 pm 0.5) times 10"17" cm molecule"-1".

Additional information

Authors: HJORTH J, JRC ISPRA ESTAB. (ITALY);OTTOBRINI G, JRC ISPRA ESTAB. (ITALY);RESTELLI G JRC ISPRA ESTAB. (ITALY), JRC ISPRA ESTAB. (ITALY)
Bibliographic Reference: JOURNAL OF PHYSICAL CHEMISTRY, VOL. 92 (1988) NO. 9, PP. 2670-2672
Record Number: 1989126110800 / Last updated on: 1989-06-01
Category: PUBLICATION
Available languages: en