Photodissociation of methylazide: Observation of triplet methylnitrene radical

An investigation of the photodissociation of methylazide at wavelengths from 292 nm to 325 nm is presented. Emission spectra and lifetime analysis show the existence of the triplet CH3N radical. A simple kinetic model is proposed to explain the observed fluorescence real time profile, which reflects the vibrational relaxation of hot radical at high pressures. The photodissociation dynamics of methylazide seems complex. The predominant channel is likely to produce CH2NH via concerted 1,2-hydrogen shift and N2 extrusion process. The triplet CH3N comes from a minor spin-forbidden channel which involves possibly strong interaction between the low-lying excited singlet and triplet states of methylazide.