Laboratory Studies of CHF2CF2CH2OH and CF3CF2CH2OH: UV and IR Absorption Cross Sections and OH Rate Coefficients between 263 and 358 K

2012 ◽  
Vol 116 (24) ◽  
pp. 6041-6050 ◽  
Author(s):  
María Antiñolo ◽  
Sergio González ◽  
Bernabé Ballesteros ◽  
José Albaladejo ◽  
Elena Jiménez
Keyword(s):  
Cross Sections ◽  
Rate Coefficients ◽  
Ir Absorption ◽  
Absorption Cross ◽  
Laboratory Studies

ChemInform Abstract: Atmospheric Fate of CF2H2, CH3CF3, CHF2CF3, and CH3CFCl2: Rate Coefficients for Reactions with OH and UV Absorption Cross Sections of CH3CFCl2.

ChemInform ◽  
2010 ◽  
Vol 22 (42) ◽  
pp. no-no
Author(s):  
R. TALUKDAR ◽  
A. MELLOUKI ◽  
T. GIERCZAK ◽  
J. B. BURKHOLDER ◽  
S. A. MCKEEN ◽  
...  
Keyword(s):  
Cross Sections ◽  
Uv Absorption ◽  
Rate Coefficients ◽  
Absorption Cross ◽  
Atmospheric Fate

Atmospheric Chemistry of 1-Methoxy 2-Propyl Acetate: UV Absorption Cross Sections, Rate Coefficients, and Products of Its Reactions with OH Radicals and Cl Atoms

2016 ◽  
Vol 120 (45) ◽  
pp. 9049-9062 ◽  
Author(s):  
Antonia G. Zogka ◽  
Abdelwahid Mellouki ◽  
Manolis N. Romanias ◽  
Yuri Bedjanian ◽  
Mahmoud Idir ◽  
...  
Keyword(s):  
Cross Sections ◽  
Atmospheric Chemistry ◽  
Uv Absorption ◽  
Rate Coefficients ◽  
Oh Radicals ◽  
Absorption Cross ◽  
Propyl Acetate ◽  
Cl Atoms

Reaction of •OH with CHCl=CH-CHF2 and its atmospheric implication for future environmental-friendly refrigerant

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Olivier Holtomo ◽  
Lydia Rhyman ◽  
Mama Nsangou ◽  
Ponnadurai Ramasami ◽  
Ousmanou Motapon
Keyword(s):  
Gas Phase ◽  
Cross Sections ◽  
Radiative Forcing ◽  
Rate Coefficient ◽  
Computational Method ◽  
Rate Coefficients ◽  
Ir Absorption ◽  
Geometrical Structures ◽  
Atmospheric Lifetime ◽  
Environmental Friendly

Abstract In order to understand the atmospheric implication of the chlorinated hydrofluoroolefin (HFO), the geometrical structures and the IR absorption cross sections of the stereoisomers 1-chloro-3,3-difluoropropene were studied using the B3LYP/6-31G(3df) and M06-2X/6-31G(3df) methods in the gas phase. The cis-trans isomerization was assessed using the M06-2X/6-311++G(3df,p)//6-31+G(3df,p) method. The latter method was also employed for thermochemistry and the rate coefficients of the reactions of •OH with the cis- and trans-isomers in the temperature ranging from 200 to 400 K. The computational method CCSD/cc-pVTZ//M06-2X/6-31+G(3df,p) was used to benchmark the rate coefficients. It turns out that, the trans-isomer is more stable than cis-isomer and the trans- to cis-isomerization is thermodynamically unfavorable. The rate coefficient follows the Gaussian law with respect to the inverse of temperature. At the global temperature of stratosphere, the calculated rate coefficients served to estimate the atmospheric lifetime along with the photochemical ozone creation potential (POCP). This yielded lifetimes of 4.31 and 7.31 days and POCPs of 3.80 and 2.23 for the cis- and trans-isomer, respectively. The radiative forcing efficiencies gave 0.0082 and 0.0152 W m−2 ppb−1 for the cis- and trans-isomer, respectively. The global warming potential approached zero for both stereoisomers at 20, 100, and 500 years time horizons.

scholarly journals First remote sensing measurements of ClOOCl along with ClO and ClONO<sub>2</sub> in activated and deactivated Arctic vortex conditions using new ClOOCl IR absorption cross sections

2010 ◽  
Vol 10 (3) ◽  
pp. 931-945 ◽  
Author(s):  
G. Wetzel ◽  
H. Oelhaf ◽  
O. Kirner ◽  
R. Ruhnke ◽  
F. Friedl-Vallon ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Cross Sections ◽  
Stratospheric Ozone ◽  
Equilibrium Constants ◽  
Active Chlorine ◽  
Late Winter ◽  
Ir Absorption ◽  
Absorption Cross ◽  
Mixing Ratios ◽  
Reservoir Species

Abstract. Active chlorine species play a dominant role in the catalytic destruction of stratospheric ozone in the polar vortices during the late winter and early spring seasons. Recently, the correct understanding of the ClO dimer cycle was challenged by the release of new laboratory absorption cross sections (Pope et al., 2007) yielding significant model underestimates of observed ClO and ozone loss (von Hobe et al., 2007). Under this aspect, nocturnal Arctic stratospheric limb emission measurements carried out by the balloon version of the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS-B) from Kiruna (Sweden) on 11 January 2001 and 20/21 March 2003 have been reanalyzed with regard to the chlorine reservoir species ClONO2 and the active species, ClO and ClOOCl (Cl2O2). New laboratory measurements of IR absorption cross sections of ClOOCl for various temperatures and pressures allowed for the first time the retrieval of ClOOCl mixing ratios from remote sensing measurements. High values of active chlorine (ClOx) of roughly 2.3 ppbv at 20 km were observed by MIPAS-B in the cold mid-winter Arctic vortex on 11 January 2001. While nighttime ClOOCl shows enhanced values of nearly 1.1 ppbv at 20 km, ClONO2 mixing ratios are less than 0.1 ppbv at this altitude. In contrast, high ClONO2 mixing ratios of nearly 2.4 ppbv at 20 km have been observed in the late winter Arctic vortex on 20 March 2003. No significant ClOx amounts are detectable on this date since most of the active chlorine has already recovered to its main reservoir species ClONO2. The observed values of ClOx and ClONO2 are in line with the established polar chlorine chemistry. The thermal equilibrium constants between the dimer formation and its dissociation, as derived from the balloon measurements, are on the lower side of reported data and in good agreement with values recommended by von Hobe et al. (2007). Calculations with the ECHAM/MESSy Atmospheric Chemistry model (EMAC) using established kinetics show similar chlorine activation and deactivation, compared to the measurements in January 2001 and March 2003, respectively.

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