Mechanism of thermolysis of hydroxylamino-dinitroethylenes

Quantum chemical investigation of the 1‐methyl‐ and 1‐neopentyl‐2‐methoxydiazene‐1‐oxides thermal decomposition mechanisms

“…Both of these calculation levels are versions of the CCSD method and produce similar results. The calculation level CCSD/aug‐cc‐pVDZ//PBE0/cc‐pVDZ was chosen because for diaminodinitroethylene (DADNE) and its various derivatives it reproduced well the results obtained at higher calculation levels, [ 30–34 ] and these data correspond to the experiment. According to Krisyuk and Krisyuk et al, [ 31,33 ] it is sufficient to use the CCSD method for this kind of calculations.…”

“…According to Krisyuk and Krisyuk et al, [ 31,33 ] it is sufficient to use the CCSD method for this kind of calculations. In addition, it was shown in Krisyuk and Sypko [ 34 ] that both at the stage of preliminary calculations and in single‐point energy calculations, the application of double zeta‐basis and triple zeta‐basis gives almost identical values of the activation enthalpies of DADNE thermolysis reactions. It also turned out that the choice of geometry optimization method (different DFT methods or CCSD itself) has little effect on the final result.…”

“…It also turned out that the choice of geometry optimization method (different DFT methods or CCSD itself) has little effect on the final result. [ 34 ] Thermodynamic energy corrections were calculated by the MOLTRAN software package [ 35 ] using normal vibration frequencies.…”