Rotationally resolved B–X electronic spectra of both conformers of the 1-propoxy radical

Five bands of the B̃–X̃ laser induced fluorescence spectrum of jet-cooled 1-propoxy radical have been recorded with a spectral resolution of ≈200 MHz. The resolved rotational and fine structure of these bands has been assigned and analyzed providing rotational constants for both the X̃ and B̃ states as well as components of the electron spin-rotation tensor in the X̃ state. By comparison of these constants with ones obtained from quantum chemistry calculations, two bands have been assigned to the gauche (G) conformer of 1-propoxy and 3 bands to the trans (T) conformer. The spectrum of each conformer abruptly terminates after the excitation of a single C–O stretch.