Centrifugal Distortion Analysis of Hypofluorous Acid: HOF and DOF

The millimeter wave rotational spectrum of hypofluorous acid displays sizeable distortion effects. More than forty lines each for both HOF and DOF including a‐ and b‐type transitions have been measured. A semirigid rotor Hamiltonian, which includes the quartic distortion terms, was employed to fit the spectrum. The special constants (in MHz) in the notation of Watson are for $\mathrm{HOF}{\text{: Ã= 585\hspace{0.17em}631.20,\hspace{0.17em}B̃= 26\hspace{0.17em}760.31,\hspace{0.17em}C̃= 25\hspace{0.17em}510.19, Δ}}_J{\text{= 0.09414, Δ}}_{\mathrm{JK}}{\text{= 2.4146, Δ}}_K{\text{= 82.52, δ}}_J\text{= 0.00432}$ and ${\delta }_K\text{= 1.120}$ . For $\mathrm{DOF}{\text{: Ã= 316\hspace{0.17em}096.02, B̃= 25\hspace{0.17em}593.91, C̃= 23\hspace{0.17em}585.28, Δ}}_J{\text{= 0.07903, Δ}}_{\mathrm{JK}}{\text{= 1.7349, Δ}}_K{\text{= 24.82, δ}}_J\text{= 0.005933}$ and ${\delta }_K\text{= 1.183.}$ Corrections to Ã, B̃, and C̃ given above have been applied to obtain the effective moments of inertia, and the structure is recalculated.