THE EFFECT OF LARGE AMPLITUDE VIBRATIONS ON RENNER EFFECT AND SPIN-ORBIT INTERACTION IN $AH_{2}$ MOLECULES

Abstract

The theory of Renner and spin-orbit coupling has previously been applied to the limiting cases of semi-rigid bent molecules, and of linear molecules. However, recently in the analysis of the electronic spectra of $PH_{2}$ and $H_{2} S^{+}$ the bent molecule approximation has been shown to be inadequate and the coupling demonstrated to be intermediate between the two cases mentioned above. A model has been developed which accounts for the effects of the large amplitude vibration on the ro-vibronic energy level pattern. Some numerical results of the application to the $PH_{2}$ and $H_{2} S^{+}$ problems are presented, and the limitations of the model are discussed.