Quantum-chemical modeling of hydrazine photolysis in the presence of
triplet nitromethane

Introductions
The study is devoted to the photochemically initiated interaction
between nitromethane and hydrazine. The reaction mechanism includes an
oxygen atom transfer from the triplet state nitrocompound to N-atom of
organic nitrogen-containing compounds.
Research methods
Quantum-chemical calculations were carried out using the Gaussian 09
software package. The calculations included the DFT methods such as the
B3LYP, B3PW91 and ωB97XD in combination with various basis sets.
Particular attention was paid to the search for transition states
structures.
Research Results
As a result of the study, the following tasks were successfully solved:
the mechanism of photochemical transfer of an oxygen atom from a triplet
nitromethane molecule to a hydrazine molecule was determined, the
geometric characteristics of all reaction participants, including
reagents and the transition state, the energy barrier of the process was
calculated, and a detailed analysis of the spin density distribution was
carried out.

The reaction scheme was proposed as:

RNO2 + hv => 1RNO2* ~~isc~~> 3RNO2

3RNO2 + R1R2N - NR3N4 => 3[RN(O)...O…NR1R2 - NR3R4]

3[RN(O)...O…NR1R2 -- NR3R4] ~~isc~~> RN=O + O=NR1R2- NR3R4
Conclusions
The research proved the direct oxygen atom transfer as the main reaction pathway without charge transfer processes. Calculated activation energy values confirm the proposed mechanism feasibility. These results provide a basis for developing innovative nitrogen-containing compounds disposal methods.