The supporting information includes:
Figures SI-1 to SI-4: Plots of the kinetic data for the alkyl esters according to eq (1) in the manuscript.
1.0
ln[(ester)to / (ester)t]
0.8
0.6
0.4
Ethyl Butanoate
0.2
Ethyl propanoate
Ethyl ethanoate
0.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
ln[(ethene)to / (ethene)t
Fig SI-1 Examples of plots of the kinetic data for the reactions of Cl atoms with ethyl butanoate, ethyl
propanoate, and ethyl ethanoate relative to the reaction of Cl with ethene obtained at (298 ± 2) K
and atmospheric pressure using in situ FTIR for the analysis
1.0
ln[(ester)to / (ester)t]
0.8
0.6
0.4
Isopropyl ethanoate
1,1-Dimethyl ethylethanoate
Methyl-2,2-methylpropanoate
0.2
Methyl-3-methylbutanoate
Ethyl-3-methylbutanoate
0.0
0.0
1.0
2.0
3.0
4.0
ln[(ethene)to / (ethene)t
Fig SI-2 Examples of plots of the kinetic data for the reactions of Cl atoms with isopropyl ethanoate,
1,1-dimethyl ethylethanoate, methyl-2,2-methylpropanoate, methyl-3-methylbutanoate and ethyl3-methylbutanoate relative to the reaction of Cl with ethene obtained at (298 ± 2) K and
atmospheric pressure using in situ FTIR for the analysis
2.0
Pentyl ethanoate
1.8
Butyl ethanoate
ln[(ester)to/(ester)t]
1.6
Propyl ethanoate
1.4
Propyl propanoate
1.2
Methyl-2-methylpentanoate
1.0
0.8
0.6
0.4
0.2
0.0
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
ln[(ethene)to / (ethene)t
Fig SI-3 Examples of plots of the kinetic data for the reactions of Cl atoms with pentyl ethanoate,
butyl ethanoate, propyl ethanoate, propyl propanoate and methyl-2-methylpentanoate relative to
the reaction of Cl with ethene obtained at (298 ± 2) K and atmospheric pressure using in situ FTIR for
the analysis
1.2
Ethyl propanoate
1.0
ln[(ester)to / (ester)t]
Ethyl-2-methylpropanoate
0.8
Ethyl-2,2-dimethylpropanoate
0.6
0.4
0.2
0.0
0.0
0.5
1.0
1.5
2.0
2.5
ln[(ethene)to / (ethene)t
Fig SI-4 Examples of plots of the kinetic data for the reactions of Cl atoms with ethyl propanoate,
ethyl-2-methylpropanoate, and ethyl-2-2-dimethylpropanoate relative to the reaction of Cl with
ethene obtained at (298 ± 2) K and atmospheric pressure using in situ FTIR for the analysis Table
Table SI.1. Comparison of experimental rate coefficients, kexp, determined in this work for the
reaction of Cl atoms with those calculated using SAR relationships. The rate coefficients are in units
of 10-11 cm3 molecule-1 s-1. The kSAR values are those given in Table 2 in the main text. The kSAR_NEW are
the values obtained using preliminary substituent factors derived from the rate coefficient
measurements reported here and with the exception of F(-C(=O)OR are not recommendations.
Ester
O
kSARii)
kSAR_NEWii)
1.88
2.15
(7.70 ± 0.83)
(7.35 ± 0.65)i)
6.18
6.45
(12.00 ± 1.62)
(13.23 ± 1.54)i)
12.14
12.41
(17.90 ± 1.53)
17.34
17.61
(2.84 ± 0.35)
2..33
2.60
(2.04 ± 0.23)
(1.75 ± 0.19) i)
7.99
2.29
(4.19 ± 0.48)
4.70
3.68
(9.84 ± 1.18)
10.01
9.07
(3.72 ± 0.43)
(4.13 ± 0.38) i)
5.70
4.61
(6.08 ± 0.67)
(6.56 ± 0.60) i)
7.23
6.14
(3.76 ± 0.33)
(3.79 ± 0.40) i)
8.08
3.81
(5.35 ± 0.56)
9.61
5.34
(10.45 ± 0.84)
11.22
7.71
(8.07 ± 1.11)
(10.64 ± 1.09) i)
10.53
8.17
(14.10 ± 1.19)
13.77
11.94
(12.50 ± 1.41)
(12.84 ± 0.65) i)
12.06
9.70
(13.97 ± 1.59)
17.44
16.57
(17.20 ± 1.95)
18.97
18.00
O
ethyl ethanoate
O
O
propyl ethanoate
O
O
butyl ethanoate
O
pentyl ethanoate
k
(this work)
(1.71 ± 0.20)
O
O
O
isopropyl ethanoate
O
O
tert-butyl ethanoate
O
ethyl propanoate
O
O
O
propyl propanoate
O
O
methyl-2-methyl-propanoate
O
O
ethyl-2-methyl-propanoate
O
O
methyl-2,2-dimethyl-propanoate
O
O
ethyl-2,2-dimethyl-propanoate
O
ethyl butanoate
O
O
O
methyl-3-methyl-butanoate
O
O
ethyl-2-methyl-butanoate
O
ethyl-3-methyl-butanoate
O
O
O
methyl-2-methyl-pentanoate
O
O
ethyl-2-methyl-pentanoate
i)
determined using GC-FID the other values were determined using FTIR
ii)
calculated as described in the main text using the SAR of Aschmann and Atkinson (1995) and the substituent factors
F(CH3C(O)O-) = 0.066, F(CH3C(O)OCH2-) = 0.36, and F(CH3C(O)OCH<) = 0.27 from Xing et al. (2009) and F(-CO-) = 0.04 from
Cuevas et al. (2005).
iii)
calculated using the SAR of Aschmann and Atkinson (1995) and the substituent factors: F(-CH2-C(O)OR) = 0.28 (derived from the
rate coefficient for ethyl propanoate); F( >CHC(=O)OR) = 0.55 (derived from the rate coefficient for methyl-2methylpropanoate); F(≥C-C(=O)OR) = 0.36 (derived from the rate coefficient for methyl-2,2-dimethylpropanoate); F(-C(=O)OR =
0.12 (described in text); RC(=O)OC≤ = 0.19 (described in text).