DETERMINATION OF $A_{O}$ FOR SYMMETRIC TOP MOLECULES

Abstract

The problems connected with the determination of the axial rotational constant. $A_{o}$, of symmetric top molecules are well known: selection rules generally forbid the observation of transitions which would allow the determination of $A_{o}$ in the ground vibrational state or, of $A_{v}$ in the excited states. A new method of determining $A_{o}$ from high resolution vibration rotation spectra will be presented and the advantages of this method will be discussed.