species including C]O oreOH moiety has relatively higher binding
energies (Clark et al., 2008) which could enhance the RO2.H2O selfreaction
and cross-reaction (RO2.H2O þ HO2/R
́
O2) rate co-efficient.
Modest enhancements in rate coefficient would not be so important
of course but a significant increase (e.g. a factor of 2) in any of
the rate coefficients with NO, HO2 or other RO2 with the water
complexed RO2 species or a change in dominant product channels
could be important. The significance of the RO2.H2O complexation
can be assessed by calculating the enhanced loss of RO2 through the
reaction with NO or through peroxy radical cross reactions due to
the existence of RO2.H2O in the troposphere. Considering the
increased rate coefficient (a factor of 2), the complexation will
enhance the production of O3, organic nitrates (RONO2), organic
hydroperoxides (ROOH) in the lower troposphere by 12% (land) to
14% (ocean). It is of course not possible to speculate further without
experimental and/or theoretical studies to fill in the gaps in our
knowledge with respect to rate coefficient enhancements and
product channels. However, this study suggests that such experimental
measurements on the kinetics and products of the reaction
between RO2.H2O and NO, RO2/HO2 are worthy of investigation