STARK SPECTROSCOPY OF $^{13}CD_{3}OH$ AND $CH_{3}OD$ WITH THE HCN LASER.

Laser Stark Spectra of $^{13}CD_{3}OH$ and $CH_{3}OD$ were investigated at the $\\lambda = 311 \\mu m$ and 337 $\\mu m$ lines of the HCN laser. The spectra were taken for both parallel and perpendicular polarizations at Stark electric fields up to 60000 V/cm. For $^{13}CD_{3}OH$, the extensive series of absorption lines observed at 311 $\\mu m$ were assigned to the $J = 8$ to 12 members of the $K = 2 \\leftarrow 3 E_{1}$ Q branch in the $v_{t} = 1$ torsional state. One of the resonances observed at $337 \\mu m$ was tentatively identified as the $J_{k} - 18_{2} \\leftarrow 17_{1}A; v_{t} = 0$ transition. For $CH_{3}OD$, numerous families of resonances were observed at both of the laser lines. The Q branch transition observed at $311 \\mu m$ was assigned as $J_{k} = 18_{1} \\leftarrow 18_{0} E_{2}, v_{t} = 1$ torsional state. Zero field frequencies for all the assigned transitions are given with improved accuracy over those calculated from available molecular constants.