F. Ito, T. Nakanaga, H. Takeo, K. Essig, and H. Jones
[J. Mol. Spectros., Vol. 174, pp. 417-424, 1995]

An FTIR absorption spectrum of the fundamental band of the AsO radical in its X²Pi state was measured in the 900-1100 cm^-1 region with an apodized resolution of 0.006 cm^-1. About 1000 transitions were assigned, based on our previous work, but some discrepancies were found in the assignments of the Pi_3/2-Pi_3/2 transitions. The transitions were fitted to a ²Pi Hamiltonian with Hund's case (a) coupling to redetermine the molecular constants in the electronic ground state, including centrifugal distortion of the spin-orbit coupling constants. The r-dependence of the spin-orbit constant A(r) was also determined experimentally.