Knowledge Bank

The microwave spectra of the duetero ammonias $NH2D$ and $ND2H$ have been investigated by means of a millimeter and submillimeter wave spectrometer which we have described previously at this meeting. The spectra of these light asymmetric rotors consists of doublets which result from a splitting of the rotational energy levels by the molecular inversion. Watson’s formulation of the rotation-distortion Hamiltonian has been used to analyze the rotational spectrum of these molecules. An accurate analysis of the inversion splittings, which are strongly dependent upon the rotational energy state, has been used to confirm the assignment of the rotation-inversion transitions.