THE MICROWAVE SPECTRUM OF NORMAL PROPYL IODIDE.

Abstract

The microwave spectrum of normal propyl iodide has been studied in the spectral region from 18 GHz to 36 GHz. The observed spectrum is accounted for by the presence of two rotational isomers, the gauche and trans forms of the molecule. Because of the great mass of the iodine atom, both rotational isomers are very nearly symmetric prolate rotors. The trans form spectrum consists of the $J \rightarrow J +1, \Delta K=0 R^{a}$ transitions, of which only the $K = 1$ lines are resolved; the gauche spectrum exhibits in addition to these $R^{a}$ transitions a series of $Q^{b}$ transitions $J_{1,J-1}\rightarrow J_{2J-2}$. Results of the spectral analysis will be given, and the molecular geometry will be discussed.