This is a pulse program for one-dimensional 3Q-MAS experiment whatever the quadrupolar nuclei with half-integer spin I. The echo position is tau2 = k*tau1 where:
| I | 3/2 | 5/2 | 7/2 | 9/2 |
|---|---|---|---|---|
| k | 7/9 | 19/12 | 101/45 | 91/36 |
The delay tau1 should be very short, about 10 µs. The pulse lengths p1 and p2 must be optimized in order to obtain the biggest echo amplitude. In this pulse program, the CYCLOPS procedure is missing. As a result, the image of the line in the spectrum should be observed if the spectrometer frequency differs with the Larmor frequency.
ze
2 d1 tlo ; recycle duration d1
; tlo set to drive HP X amplifier
10u:c4
p1:t:c4 ph1 ; the first-pulse duration p1
d6:c4 ; spacing between pulses
p2:t:c4 ph2 ; the second-pulse duration p2
2u:c4
d7 ph0:r ; acquisition delay
3u adc
aq ; acquisition
1m
rcyc=2 ph3 ; loop to 2, NS times for averaging
wr #0
exit
ph0= 0
ph1=(6) 0 1 2 3 4 5 ; p1 pulse phase
ph2= 0 ; p2 pulse phase
ph3= 0 2 0 2 0 2 ; receiver phase