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

Thirteen far IR laser lines in CH
3
OH, optically pumped by a CO
2
laser, have been assigned to
a
- and
b
-type transitions in ν
5
CO-stretch band. Identification procedures used were: a frequency match between the CO
2
pump and CH
3
OH absorption, frequency match of laser lines and CH
3
OH ν
5
transitions, polarization of far IR radiation, cascade and competition effects between far IR laser lines, and frequency consistencies. An improved set of molecular constants for ν
5
transitions were also obtained.