Knowledge Bank

The vapor phase infrared spectrum of tetrolonitrile, $CH3C\equiv CC\equiv N$, has been observed from 4000 to $400cm-1$. This molecule is a symmetric top with $C3v$ symmetry. Four of the six $A1$ fundamentals are observed as parallel bands at $2941,2338,2274$ and about $1385cm-1$, and four of the six E fundamentals appear as perpendicular bands at 2988, 1445, 1029 and $500cm-1$. The two bands at 2338 and $2274cm-1$ are of equal intensity and indicate a high degree of mixing in the nitrile and acetylenic stretching vibrations. Coriolis coupling constants that could be measured are $\zeta 7=0.07,\zeta 8=-0.31$ and $\zeta 9=0.43$. This work was performed under the auspices of the U.S. Atomic Energy Commission.