Photochemistry of NH₂NO₂ and implications for chemistry in the atmosphere

Recent studies have indicated that nitramide (NH2NO2) may be formed more plentifully in the atmosphere than previously thought, while also being a missing source of greenhouse gas nitrous oxide (N2O) via catalyzed isomerization. To validate importance NH2NO2 Earth’s atmosphere, ground and first electronic excited states were characterized its photochemistry was investigated using multireference coupled cluster methods. is non-planar singlet multiplicity state exhibiting large out-of-plane rotation triplet state. One-dimensional cuts adiabatic potential energy surface calculated MRCI+Q method show low-lying with minima their along N–N N–O bond coordinates. Due to vertical excitation energies 225–180 nm region, photochemical processes will not compete troposphere, causing N2O production predicted major removal process NH2NO2. In upper photodissociation form NH2NO + O (3P) suggested pathway.