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The l-doubling spectra of monodeuteroacetylene have been obtained in the $ v_{4}=1$ (C-D bend) and $ v_{5}=1$ (C-H bend) states of the molecule with resolution sufficient to determine the deuterium nuclear quadrupole coupling constants. The spectroscopic constants obtained from the J = 1 rotational level are: [FIGURE] These results are in essential agreement with the microwave work of Hirota, et. $al.1$ in which $Bv$ was determined along with $\mu$ and the l-doubling constant. A vector-tensor model of the electron distribution is used to discuss these results, and it is shown that they are inconsistant with the assumption of a cylindrical electron distribution about the C-D bond axis. 1.J. Phys. Chem., 84, 1793, (1980)