Knowledge Bank

The microwave spectrum of $\mathrm{<mrow\; data-mjx-texclass="ORD">12</mrow>}CH312C15N$ and $\mathrm{<mrow\; data-mjx-texclass="ORD">13</mrow>}CH313C15N$ for $1\le J\le 5$ over the freouency range of 17-95 GHZ was investigated for the vibrational states $n\nu 8,n=1,2$ and $3,\nu 7$ and $\nu 4$ to determine if systematic differences between theory and experiment as had been found for the 1$\mathrm{<mrow\; data-mjx-texclass="ORD">12</mrow>}CH313C15N$ were also present in these two molecules for the $A-.(K=\ell =+1)$, and $A-.(K=\ell =-1$. vibrational species. Large departures observed in the rotational spectra of the molecular species of $\mathrm{<mrow\; data-mjx-texclass="ORD">13</mrow>}C$ and $\mathrm{<mrow\; data-mjx-texclass="ORD">15</mrow>}N$ substituted methyl cyanide seem to provide basis for a study of fundamental interactions in molecular systems with $C3v$, symmetry. The presence of each isotoe alters the frequency position of each internal mode for the molecule and this substitution seems to bring some energy levels into closer resonance conditions with ensuing strong interaction between energy states.