Table 1.

Reactions considered in the time-averaged model and their rate constants.

No.	Reaction	Rate constant	Source
1	O3 + alkenei → intermediates → OH + SCI + products	Table S1	1
2	OH + VOCi → products	Table S1	1
3	O3 + NO → NO2 + O2	kNO–O3 = 1.6 ppb–1 h–1	2
4	O3 + NO2 → NO3 + O2	kNO2–O3 = 0.0028 ppb–1 h–1	2
5	OH + NO + M → HONO + M	kNO–OH = 2800 ppb–1 h–1	2
6	OH + NO2 + M → HONO2 + M	kNO2–OH = 5300 ppb–1 h–1	2
7	OH + NO3 → HO2 + NO2	kNO3–OH = 2000 ppb–1 h–1	2
8	OH + OH → H2O + O	kOH–OH = 170 ppb–1 h–1	2
9	OH + O3 → HO2 + O2	kO3–OH = 6.0 ppb–1 h–1	2
10	NO3 + VOCi → products	Table S1	1
11	NO3 + NO → 2NO2	kNO–NO3 = 2300 ppb–1 h–1	2
12	NO3 + NO2 → N2O5	kNO2–NO3 = 180 ppb–1 h–1	2
13	N2O5 → NO3 + NO2	kN2O5(d) = 250 h–1	2
14	$2{\mathrm{NO}}_2\left(\mathrm{g}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{aq}\right)\to \mathrm{HONO}\left(\mathrm{aq}\right)+{\mathrm{H}}^{+}+{\mathrm{NO}}_3^{-}$	Table 2 and kNO2·surf(HONO) = 0.055 h–1	3
15	${\mathrm{NO}}_2\left(\mathrm{g}\right)+\mathrm{HONO}\left(\mathrm{aq}\right)\to {\mathrm{H}}^{+}+{\mathrm{NO}}_3^{-}+\mathrm{NO}$	Table 2 and kNO2·surf(NO) = 0.055 h–1	3
16	HONO(aq) ↔ HONO(g)	Not considered in time-averaged model
17	HONO + hv → OH + NO	Table 2	4
18	OH + HONO → H2O + NO2	kHONO-OH = 430 ppb–1 h–1	2
19	SCI + NO2 → NO3 + products	kNO2–SCI = 600 ppb–1 h–1	5
20	SCI + H2O → products	kH2O–SCI = 0.0089 ppb–1 h–1	5

1. Oxidant/VOC reaction rates are from Atkinson and Arey (2003) and the Master Chemical Mechanism v3.2. See the Supplementary Information for specific information.

2. Atkinson et al., 1992b.

3. Spicer et al., 1993.

4. Alvarez et al., 2013.

5. Welz et al., 2012.