The gas-phase vibration-rotation emission spectrum of the (\mathrm{CD}) radical in the (X^{2} \Pi) state was observed in the (1832-2150 \mathrm{~cm}^{-1}) region with a high-resolution Fourier transform spectrometer. The CD radicals were generated by a dc discharge in a (\mathrm{CD}{4}) and He mixture. The spectra of the (v=1-0) and (2-1) bands were analyzed by an effective Hamiltonian in Hund's case (a) parity-conserving basis set written in the (\mathbf{N}^{2})-formalism. Molecular constants of the vibrationally excited states were determined for the first time with a high precision, and the equilibrium molecular constants were determined: (\omega{\mathrm{e}}=2100.3457(10) \mathrm{cm}^{-1}, \omega_{\mathrm{e}} x_{\mathrm{c}}=34.15582(39) \mathrm{cm}^{-1}, B_{\mathrm{e}}) (=7.807826(33) \mathrm{cm}^{-1}), and (\alpha_{\mathrm{c}}=0.212255(80) \mathrm{cm}^{-1}), with one standard deviation given in parentheses. The internuclear distance, (r_{e}) was also determined to be (1.117915(10) \AA) from the corrected equilibrium rotational constant for the second-order electronic contribution to the rotational constant. Quantitative discussions on the Herman-Wallis effect are presented for the (\mathrm{CH}) and CD radicals. The analysis of this effect on the (\mathrm{CH}) radical led to the transition moment of (-0.190(11) \mathrm{D}) for the (v=1-0) band. e 1995 Academic Press. Inc.