Determination of Electronic Symmetry by Electric Deflection: LiO and LaO

Abstract

The focusing, by means of an electrostatic quadrupole, of polar molecules with first‐ or second‐order Stark effects is discussed. Indications of molecular electronic symmetry may be obtained from quantitative measurements of the intensity of refocusing of beams of diatomic molecules. Such measurements indicate that the ground state of LiO is Π while that of LaO is Σ. It is suggested that the optical spectroscopic data of ScO, YO, and LaO are best explained by assigning the ground states of these three molecules as ²Σ. The observed low‐lying electronic states of these molecules are interpreted in terms of a localized‐orbital picture.