FIR Laser Stark Spectroscopy of CH318OH

✍ Scribed by M. Jackson; G.R. Sudhakaran; R.M. Lees; A. Silveira; I. Mukhopadhyay

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 624 KB
• Volume: 164
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.1994.1072

✦ Synopsis

The laser Stark spectrum of ({ }^{18} \mathrm{O})-substituted methanol has been studied using the 337 - and 311 (\mu \mathrm{m}) lines of the HCN laser as well as the (195-\mu \mathrm{m}) line of the DCN laser. Numerous families of absorption lines have been observed for both parallel and perpendicular polarizations up to 60 (\mathrm{kV} / \mathrm{cm}). With the (337-\mu \mathrm{m}) line. two families of resonances are identified as (J_{K}=9_{6} \leftarrow 10_{5} E_{2}, v_{t}) (=0) and (J_{K}=1_{1} \leftarrow 2{ }{2} E{2}, v_{1}=1) transitions. The Stark shifts for the (J_{K}=96 \leftarrow 10_{5} E_{2}, v_{1}=0) transition are best represented by values of (0.893 \pm 0.020) and (1.36 \pm 0.02 \mathrm{D}) for the parallel and perpendicular components, respectively, of the electric dipole moment for (\mathrm{CH}{3}{ }^{18} \mathrm{OH}). Two families of resonances observed at (\lambda=311 \mu \mathrm{m}) are identified as the (J{K}=9_{1}^{-} \leftarrow 8_{2}^{+} A, v_{t}=1) transition, forbidden in zero field, and the (J_{K}=7_{4} \leftarrow 6_{3} A, v_{t}=0) transition. An (R)-branch transition observed with the (195-\mu \mathrm{m}) line has been identified as the (J_{K}=10_{7} \leftarrow 9_{6} A, v_{1}=0) transition. Zero-field frequencies for all the assigned transitions are given with improved accuracy over those calculated from available molecular constants. c| 1994 Academic Press. Inc.