Knowledge Bank

The microwave spectra of $CH2-CH2-NCl35,CH2-CH2NCl37$, and $C13H2-CH2NCl35$ have been investigated under high resolution. From the effective moments of inertia of these isotopic species the following structural parameters were determined: Cl-N distance $=1.754\pm 0.006\backslash AA$, C-N distance $=1.489\pm 0.006\backslash AA$, C-C distance $=1.481\pm 0.001\backslash AA$, C-H distance $=1.074\pm 0.01\backslash AA,(CNC)-(NCl)$ angle $=114.12\circ \pm 0.5\circ$, (HCH)-(CC) angle $=155.3\circ \pm 3\circ$, and (HCH) angle $\pm 112.9\circ \pm 3\circ$. The diagonal quadrupole coupling constants for the nitrogen nucleus and the complete coupling constant tensor for $Cl33$ were also determined. The latter, by its relationship to the molecular structure, shows that the N-Cl bond is not bent within an experimental uncertainty of one degree of angle. An expression in terms of 3-j and 6-j symbols is given for the general matrix element of the interaction Hamiltonian in the $I1JF1I2F$ coupling scheme.