Knowledge Bank

The ethylnitrene radical $CH3CH2N$ has been produced by the interaction of gaseous ethylazide with metastable $N2$ or Ar generated in a microwave discharge, and has been trapped in $N2$ and Ar matrices at 10 K. The UV absorption spectrum in solid nitrogen consists of a series of eleven bands beginning at 335 nm with an average vibrational interval of $320cm-1$. Intensity alternations suggest that two different vibrations are excited in the transition, probably a C-C-N bend corresponding to the observed spacing and a C-N stretch with vibrational frequency near $650cm-1$. The ESR spectrum at 8300 G indicates that ethyloitrene has a triple ground state with zero-field splitting parameters D = $1.67cm-1$ and E = $0.0033cm-1$ in a nitrogen matrix. The hyperfine splittings differ slightly in the x and y lines and have the average values of 16.0 G for N and 30.6 G for the methylene H. The spectral features associated with ethylnitrene were not observed through direct photolysis of the parent ethylazide either during or after deposition. The new optical data confirms previous speculation and expands the assignment of the UV spectrum of ethylnitrene; the high D value indicated by the ESR signals lends support to the suggestion that earlier assignments of the ESR spectrum of methylnitrene, $CH3N$, are incorrect.