ABSOLUTE FREQUENCY MEASUREMENTS OF METHANOL FROM 1.5 TO 6.5 THZ

Frequencies of 445 CH3OH rotational transitions between 1.5 and 6.5 TH z have been measured with an accuracy of one part in 10(9). The far-in frared radiation used for the measurements was generated from the radi ation of two CO2 lasers using a MIM diode as a nonlinear mixer. The hi gh resolution and sensitivity of the spectrometer also enabled us to o bserve a series of forbidden Q-branch transitions (Delta n = 1 and Del ta K = 0) for J = 12 to 26. (C) 1994 Academic Press, Inc.