Five bands of the (B) over tilde-(X) over tilde laser induced fluorescence spectrum of jet-cooled 1-propoxy radical have been recorded with a spectral resolution of approximate to200 MHz. The resolved rotational and fine structure of these bands has been assigned and analyzed providing rotational constants for both the (X) over tilde and (B) over tilde states as well as components of the electron spin-rotation tensor in the (X) over tilde 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. (C) 2003 American Institute of Physics.