Electric dipole moment of the A 2Π state of CN as measured by level anticrossing spectroscopy

Abstract
The dipole moment of the electronically excited A 2Π state of the CN radical has been measured as 0.56±0.03 D by analyzing the electric field dependence of the level anticrossing spectral linewidth. The theory of the Stark effect in this system is developed and it is shown that the broadening depends upon two parameters: the A 2Π dipole moment and the electric dipole transition moment between the A 2Π and B 2Σ+ states. The spectral linewidth is rather insensitive to the value of the transition moment and this quantity is not well determined from the experimental data.