Strong-Field Stark Effect of Asymmetric-Top Rotator

A computer program is designed to calculate the Stark effect of lower rotational energy levels of an asymmetric top rotator with an arbitrary asymmetry parameter. Instead of using the perturbation expansion formula the program obtains eigenvalues of the secular equation with external electric field. With the available computer capacity, this means calculating up to about 10th order perturbation terms. The procedure is suitable and the only practical way to calculate Stark effect with strong field. Some results on the H2S and the SO2 molecules are shown.