Laser magnetic resonance study of the gas phase reactions of OH with CO, NO, and NO2

摘要

A laser magnetic resonance spectrometer has been used in combination with a dischargehyphen;flow system to measure the gas phase reaction rates of the OH radical with CO, NO, and NO2at 296deg;K and over a pressure range 0.4ndash;5 torr. For the bimolecular reaction OH plus; CO rarr; CO2plus; H we measure a rate constant,kequals; 1.56times;10minus;13cm3sol;moleculemiddot;sec. For the termolecular reactions OH plus; NO plus;Mrarr; HNO2plus;M, Mequals; He,kequals; 4.0times;10minus;31cm6sol;molecule2middot;sec;Mequals; Ar,kequals; 4.4times;10minus;31cm6sol;molecule2middot;sec;Mequals; N2,kequals; 7.8times;10minus;31cm6sol;molecule2middot;sec. For the reaction OH plus; NO2plus; N2rarr; HNO3plus; N2,kequals; 2.9times;10minus;30cm6sol;molecule2middot;sec. Laser magnetic resonance detection of radicals is shown to be extremely sensitive, linear, and versatile. A complete description of this technique is presented with a discussion of its potential in the study of the reactions of free radicals.