2 research outputs found
Dimensional perturbation theory for vibration-rotation spectra of linear triatomic molecules
A very efficient large-order perturbation theory is formulated for the
nuclear motion of a linear triatomic molecule. To demonstrate the method, all
of the experimentally observed rotational energies, with values of almost
up to 100, for the ground and first excited vibrational states of CO and
for the ground vibrational states of NO and of OCS are calculated. All
coupling between vibration and rotation is included. The perturbation
expansions reported here are rapidly convergent. The perturbation parameter is
, where is the dimensionality of space. Increasing is
qualitatively similar to increasing the angular momentum quantum number .
Therefore, this approach is especially suited for states with high rotational
excitation. The computational cost of the method scales only as ,
where is the size of the vibrational basis set.Comment: submitted to Journal of Chemical Physics, 23 pages, REVTeX, no
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