An automated branch-assignment algorithm for rovibrational spectra of asymmetric-top molecules

There are several methods for isolating a P, Q, or R branch from the rest of the unassigned rovibrational spectrum of an asymmetric-top molecule. But at the moment, to our knowledge, once the branch has been isolated, there is no automated procedure for its assignment. Here, we present a simple semi-empirical algorithm which has proved successful in computer experiments on both S(CN)2 (a near prolate rotor) and C3H6O (a near oblate rotor.) The limits to the applicability of this method are discussed.