Experimental Study of NO Reaction with Isoprene Hydroxyalkyl Peroxy Radicals Academic Article uri icon


  • Despite the importance of isoprene hydroxy peroxy radicals (RO 2) in the conversion of NO to NO 2 and hence in tropospheric ozone formation, no direct experimental studies have been carried out to investigate the kinetics of the RO 2-NO reaction. We report the first direct laboratory study of the rate constant for the isoprene RO 2-NO reaction using a fast-flow reactor coupled to chemical ionization mass spectrometry (CIMS) detection. By directly monitoring the peroxy radical, a rate constant of (9 ± 3) × 10 -12 cm 3 molecule -1 s -1 was determined in the pressure range of 1 to 2 Torr and at a temperature of 298 ± 2 K. The measured rate constant is compared to the results of a recent theoretical prediction and indirect measurements and implications for the atmosphere are discussed.

author list (cited authors)

  • Zhang, D., Zhang, R., & North, S. W.

publication date

  • January 1, 2003 11:11 AM