Knowledge Bank

132 transitions in the $\nu 3$ (CN stretching) fundamental and the corresponding bending and stretching hotbands of the cyanate anion, ranging from P(52) to R(66), have been measured with a tunable diode laser using the velocity modulation technique. The spectra were fit to the standard linear triatomic molecule rotation-vibration Hamiltonian, yielding effective molecular parameters for the $(0000),(0110),(0200),(1000),(0001),(0111),(0201)$ and $(1001)$ states. The equilibrium rotational constant was determined to be $Be=0.385933(116)cm-1$. A comparison with condensed phase results is presented. As previously observed for $N3-$, cyanate is detected with high vibrational excitation in the bending mode, most likely as a consequence of the formation mechanism.