Knowledge Bank

Ground state rotational spectra of $CH325CICN2$ and $CH337CICN2$ have been assigned, and the derived $r0$ structural parameters are: $r(NN)=1.241\pm 0.005\backslash AA,r(CCl)=1.743\pm 0.01\backslash AA,r(CC)=1.498\pm 0.01\backslash AA,\sphericalangle CC-C-Cl=116.7\circ \pm 1.0\circ ,\sphericalangle CCN2=124.5\circ \pm 1.0\circ$, and $\sphericalangle NCN=50.2\circ \pm 0.5\circ$. The internal rotation splittings for $CH335CICN2$ yield a barrier to internal rotation of $1689\pm 10$ calories mole$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$. The Cl quadrupole coupling constants (MHz) for $CH335ClCN2$ are $\chi aa=-66.51,\chi bb=32.91,\chi cc=33.60$ and for $CH337ClCN2$ are $\chi aa=-53.07,\chi bb=26.40,\chi cc=-66.51,\chi bb=32.91,\chi cc=33.60$ and for $CH337ClCN2$ are $\chi aa-53.07,\chi bb=26.40,\chi cc=26.67$. The nitrogen quadrupole splitting were generally unresolved. The ground state rotational spectra of $(CH2D)(CH3)2N,(CH3)315N$, and $(13CH3)(CH3)2N$ have been assigned yielding the effective moments of inertia. This information has been combined with that for $(CH3)3N$ to give the following structural parameters: $r(CN)=1.451\pm 0.003\backslash AA,r(CH8)=1.109\pm 0.008\backslash AA,r(CHa)=1.088\pm 0.008\backslash AA,\sphericalangle CNC=110.9\circ \pm 0.6\circ ,\sphericalangle NCHa=111.7\circ \pm 0.4\circ ,\sphericalangle NCHa=110.1\circ \pm 0.5\circ ,\sphericalangle HaCHa=108.1\circ \pm 0.7\circ ,and\sphericalangle HaCHa=108.6\circ \pm 0.8\circ ,$ where $H2$ lies in a symmetry plane. $AC3v$ equilibrium conformation has been established and the methyl groups appear to be tilted by $1.3\circ$ toward the unshared electron pair. A mild Coriolis interaction has been observed between the lowest two vibrational states of ethylene episulfoxide.