OPTICALLY PUMPED FAR-INFRARED LASER LINES OF METHANOL ISOTOPOMERS: "CD,OH, "CH,OD, AND "CH2DOH

Twenty-seven new FIR, far-infrared, laser lines from the isotopomers of methanol: '*CD30H, "CH30D, and '2CHzDOH, were obtained by optically pumping the molecules with an efficient cw CO, laser. The CO, laser provided pumping from regular, sequence, and hot-band C& laser transitions. The 2 m long far-infrared cavity was a metal-dielectric waveguide closed by two, flat end mirrors. Several short-wavelength (below 100 pm) lines.were observed. The frequencies of 28 laser lines observed in this cavity (including new lines and already known lines) were measured with a fractional uncertainty limited by the fractional resetability of the far-infrared laser cavity, of 2 parts in lo7. Key Words: "CD30H, "CH30D, "CH2DOH, new f a r- i i e d laser lines, optically pumped far-infrared laser, laser frequencies, relative intensity, relative polarization, pump-frequency offset