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The rate constant of the reaction of NO3 radical with CF3I was determined by a relative rate method using a Fourier transform infrared (FTIR) spectrometer smog chamber with a long path length gas cell. As a result, the upper limit of the rate constant was determined to be <2.2 × 10−18 cm3 molecule−1 s−1 in 100 Torr of total pressure at 298 K, which suggests that CF3I emitted into the atmosphere accumulates during night. The rate constant of the reaction of NO3 with I(2P3/2) was also measured using time-resolved cavity ring-down spectroscopy. The rate constant showed no pressure dependence in the range of 100-500 Torr of total pressure at 298 K and was determined to be (3.9 ± 1.0) × 10−11 cm3 molecule−1 s−1. The present result is different from the previous ones and is about half of that reported most recently. From this rate constant, it is likely that the reaction of NO3 radical with I(2P3/2) does not have a much influence on the loss of I(2P3/2) and the formation cycle of IO radical in the atmosphere. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 44: 649-660, 2012 [ABSTRACT FROM AUTHOR]

The rate constant of the reaction of NO3 radical with CF3I was determined by a relative rate method using a Fourier transform infrared (FTIR) spectrometer smog chamber with a long path length gas cell. As a result, the upper limit of the rate constant was determined to be <2.2 × 10−18 cm3 molecule−1 s−1 in 100 Torr of total pressure at 298 K, which suggests that CF3I emitted into the atmosphere accumulates during night. The rate constant of the reaction of NO3 with I(2P3/2) was also measured using time-resolved cavity ring-down spectroscopy. The rate constant showed no pressure dependence in the range of 100-500 Torr of total pressure at 298 K and was determined to be (3.9 ± 1.0) × 10−11 cm3 molecule−1 s−1. The present result is different from the previous ones and is about half of that reported most recently. From this rate constant, it is likely that the reaction of NO3 radical with I(2P3/2) does not have a much influence on the loss of I(2P3/2) and the formation cycle of IO radical in the atmosphere. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 44: 649-660, 2012 [ABSTRACT FROM AUTHOR]

Abstract: The reaction of NO3 with C2H5I was studied using time-resolved cavity ring-down spectroscopy. The rate constant of NO3 +C2H5I reaction was determined to be (2.4±0.4)×10−13 cm3 molecule−1 s−1 at 298K and showed no pressure dependence in the range of 25–100Torr of N2 diluent. The determined value of the rate constant suggests that the reaction of NO3 with C2H5I would play an important role in the iodine cycle at night. [Copyright &y& Elsevier]

Abstract: We have applied time resolved cavity ring-down spectroscopy to a kinetic study of the reaction of NO3 with NO2 in 20–700Torr of N2 diluent at 298 and 283K. By fitting the data to Troe’s expression with F c =0.6, the low-pressure and high-pressure limiting rate constants of this reaction were determined to be (298K)=(3.1±0.8)×10−30 cm6 molecule−2 s−1 and (298K)=(1.6±0.3)×10−12 cm3 molecule−1 s−1. These rate constants thus determined were 10–40% larger than those recommend in the NASA/JPL database. [Copyright &y& Elsevier]

Abstract: We have applied cavity ring-down spectroscopy to a kinetic study of the reaction of NO3 with CH2I2 in 25–100Torr of N2 diluent at 298K. The rate constant of reaction of NO3 +CH2I2 is determined to be (4.0±1.2)×10−13 cm3 molecule−1 s−1 in 100Torr of N2 diluent at 298K. The rate constant increases with increasing pressure of buffer gas below 100Torr. The reaction of CH2I2 with NO3 has the potential importance at nighttime in the atmosphere. [Copyright &y& Elsevier]