FAR-INFRARED LASER STARK SPECTROSCOPY OF $^{13}CH_{3}OH$

Author Institution: New Mexico State University, Las Cruces, N. M. 88003; University of Wisconsin, La Crosse, WI 54601; University of New Brunswick, Fredericton, New Brunswick, Canada E3B5A3; Centre for Advanced Technology, Indore 452013, M. P. IndiaThe laser Stark spectrum of $^{13}CH_{3}OH$ has been studied using the 311 and $337 \mu m$ lines of the HCN laser as well as the 190 and $195 \mu m$ lines of the DCN laser. Numerous families of absorption lines have been observed for both parallel and perpendicular polarizations up to 60.000 V/cm. With the $195 \mu m$ line, two families of resonances are identified as $J_{k} = 10_{2} \leftarrow 9_{6} A_{\ast} \nu_{t} = 0$ and $J_{k} = 27_{9} \leftarrow 27_{8} E_{1} \nu_{1} = 0$ Using the $337 \mu m$ line, two transitions are assigned as $J_{k} = 14_{g} \leftarrow 15, A, \nu_{l} = 0$ and $J_{k} = 19_{3} \leftarrow 18_{3} E_{l} \nu_{t} = 1$. Further investigation of the $^{13}CH_{3}OH$ spectra using the $311 \mu m$ has allowed an additional transition to be identified as $J_{k} = 15_{3} \leftarrow 14_{2} A^{\prime}, \nu_{t} = 0$. Several additional families have been observed with each of the laser lines and are currently under investigation. Zerofield frequencies for all of the assigned transitions are given with improved accuracy over those calculated from the available molecular constants