Assignments of the high power optically pumped CW laser lines of CH3OH

Thirteen far IR laser lines in CH3OH, optically pumped by a CO2laser, have been assigned to - and -type transitions in ν5CO-stretch band. Identification procedures used were: a frequency match between the CO2pump and CH3OH absorption, frequency match of laser lines and CH3OH ν5transitions, polarization of far IR radiation, cascade and competition effects between far IR laser lines, and frequency consistencies. An improved set of molecular constants for ν5transitions were also obtained.