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The three hydrogen-deuterium isotopomers of tetrafluorocyclobutene are near-prolate symmetric tops. The two $C2v$ species are unusual in having their dipole axes perpendicular to the pseudo-figure axis, $Ia$. In addition, the $Ia$ axis is parallel to the dipole axis in the $d0$ species but perpendicular to it in the $d2$ species. 1 Under these circumstances B-type and C-type band shapes are essentially indistinguishable in gas-phase infrared spectra. Nonetheless, a reasonably complete and convincing assignment of vibrational fundamentals can be made from the infrared and Raman spectra of the three isotopomers, considered together. For the $d0$ species selection rules and fundamentals (in $cm-1$) are ($a1$; IR, C-type; R, pol) 3154, 1564, 1350, 1155, 1025, 755, 500, 277; ($a2$; IR, -; R, dp) --, 966, 348, --, 132; ($b1$ IR, A-type; R, dp) 3108, 1338, 1177, 1058, 730, 614, 431; ($b2$ IR, B-type; R, dp) 1340, 799, 366, 208.