HIGH RESOLUTION INFRARED KINETIC SPECTROSCOPY: QUASILINEARITY OF HCCN

Abstract

Author Institution: Department of Chemistry and Rice Quantum Institute, Rice UniversityThe C-H stretching fundamental of HCCN has been observed under high resolution. This transient molecule was produced by the flash photolysis of dibromoacetonitrile ($Br_{2}$HCCN) at 193 nm and its spectrum probed using a color center laser. Rotational analysis of the $\nu_{1}$ fundamental places its origin at $3246.657 cm^{-1}$. Several hot bands associated with the bending vibrations have been observed and two, $\nu_{1}+\nu_{5}-\nu_{5}$ and $\nu_{1}+\nu_{4}-\nu_{4}$, have been rotationally analyzed. The energy of the $\nu_{5}$ band was obtained by measuring the intensity of the $\nu_{1}+\nu_{5}-\nu_{5}$ band relative to the fundamental, assuming a Boltzmann distribution. A comparison of this energy with that of quasilinear fulminic acid, HCNO, suggests a similar floppy HCX bending potential