Table 1.

Estimates of direct photolysis rates in mid-latitude mid-summer sunlight.

compound	$2.303{\text{ΣI}}_{\lambda }{\mathrm{\epsilon }}_{\lambda }\text{Δ}\lambda \left({\text{s}}^{-1}\right)$a	matrix for UV-vis spectrum	$\mathit{\varphi }$b	half-life
				calculated if ϕ = 1	calculated using selected ϕ	natural sunlight experimentc
trifluralin	8.1 × 10−02	Methanol [21]	1.4 × 10−3 at 310–410 nm [22], 6 × 10−1 at 254 nm [23]	9 s	1.7 h	2 h
RDX	2.7 × 10−05	Acetonitrile [24]	0.16 at 313 nm [25]	7 h	1.8 d
	7.2 × 10−06	Acetonitrile [26]		1.1 d	7 d
	4.6 × 10−05	Water [25]		4 h	1.1 d
metolachlor	1.6 × 10−06	Water [27]	9.6 × 10−3 at solar range [28], 3 × 10−5 at 313 nm [28]	5 d	1.5 y	9 d

Note:

^acalculated using a reference spectrum of June 21 daily irradiance at 40 °N [18] and UV–vis spectra from the literature.

^bThe selected φ for half-life calculation is underlined.

^cexperiment conducted in spring at 45 °N, intensity approximately similar as the used reference solar spectrum [29].