Communication: The permanent electric dipole moment of thorium monoxide, ThO

The optical Stark spectrum of the E(0(+)) - X-1 Sigma(+) (1,0) band of thorium monoxide, ThO, was recorded and analyzed to determine the permanent electric dipole moments, mu, for the E(0(+)) (v = 1) and X-1 Sigma(+) (v = 0) states. Values of 2.782 +/- 0.012 D (X) and 3.534 +/- 0.010 D (E) were obtained. The uncertainties are 2 sigma statistical error. The systematic errors are estimated to be less than 1%. The experimental results are used to access the quality of electronic structure calculations of the properties of the X-1 Sigma(+) (v = 0) state. (C) 2011 American Institute of Physics. [doi:10.1063/1.3533274]