Dmf (vnmr parameter)
From NMR Wiki
dmf - (in Varian vnmr sofware) decoupler modulation frequency for decoupler channel #1 in Varian vnmr software
dmf equals 1/(width of 90 pulse) at power level dpwr for that channel
Analogously, there are parameters dmf2 and dmf3 - for decoupler channels #2 and #3 and dpwr2 and dpwr3, respectively