A Theoretical Consideration on the Predissociation of Ammonia

Abstract

The predissociation of NH₃ has been discussed from the molecular orbital consideration utilizing Shuler's method. The molecule, at first, absorbs the light of about 2000Â? and is excited to the first excited state ¹A₁. In this state the planar molecular structure is found more stable than the pyramidal one. After having taken the former structure the molecule dissociates to NH₂(²B₁) plus H(²S), passing through the intermediate structure with symmetry C_2v. Meanwhile the property of the highest singly occupied orbital changes from 3s-like to antibonding on account of the crossing (in the approximation of single configuration) of the potential energy curves.