15min:

ANNIE HANSSON, Stockholm University, AlbaNova University Center, Department of Physics, SE-10691 Stockholm, Sweden; JAMES K. G. WATSON, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario, Canada K1A 0R6.

The Hönl-London factors are the factors dependent on the rotational quantum numbers in formulas for intensities of rovibronic transitions. A table of Hönl-London factors for singlet-singlet transitions of a diatomic molecule was given by Herzberg, and reproduced in other books. Standard definitions of transition moments and sum rules were proposed by Whiting and Nicholls\footnoteE.~E.~Whiting and R.~W.~Nicholls, Astrophys.~J.~Suppl.~Ser. \textbf27, 1 (1974); E. E. Whiting, A. Schadee, J. B. Tatum, J. T. Hougen and R. W. Nicholls, J. Mol. Spectrosc. \textbf80, 249 (1980)., but there does not seem to be a published table of the corresponding individual Hönl-London factors. Here we show that for rotational transitions between levels of definite parity the values in Herzberg's table should be multiplied by 2 for all perpendicular vibronic transitions, with an additional factor of 2 for - and - transitions. The results are consistent with the Whiting-Nicholls conventions.^c