Photolysis of Dimethylnitrosamine in the Gas Phase

Article abstract of DOI:10.1002/hlca.19810640405

Photodecomposition of dimethylnitrosamine in the gas phase ( 1 Torr) has been investigated following irradiation into the S₁(n?^*) <- S₀(363.5 nm) and S₂(??'^*) <- S₀(248.1 nm) transitions at room temperature.With a quantum yield of unity, excitation into the S₁ state yields the fragments (CH3)2N and NO which then recombine leaving no photoproducts.The addition of O2 results in only one photoproduct, (CH3)2NNO2.Irradiating into the S₂ state, the products CH2=N-CH3, (CH2=N-CH3)3, CH2=NOH, N2O, NO, H2, and N2 were identified by capillary gas chromatography mass spectrometry.In the presence of N2 as a buffer gas the photoproducts are only CH2=N-CH3, (CH2=N-CH3)3, N2O, and H2.For both excitation conditions a mechanism is proposed involving cleavage of the N,N-bond as the main primary photolytic process.