A molecular beam-optical Stark study of the A 2Π–X 2Σ band system of YO

Abstract
The permanent electric dipole moments of yttrium monoxide YO in its X 2Σ+, A 2Π3/2, and A 2Π1/2 states have been experimentally determined from an analysis of the Stark shifts in the optical spectrum of a molecular beam sample. The determined values are 4.45(7), 3.68(2), and 3.22(8) D, respectively. The results are discussed in terms of bonding models for YO and are compared to recent theoretical predictions.