4.11 MREV8 and CYLMREV - Multiple Pulse Line Narrowing (8-pulse cycle)
01-999162-00 C0402
VNMR 6.1C User Guide: Solid-State NMR
70
4.11 MREV8 and CYLMREV - Multiple Pulse Line Narrowing
(8-pulse cycle)
MREV8 (
) is a sequence used for
1
H CRAMPS. CYLMREV is a modification
that allows quadrature detection with the transmitter in the center of the spectrum. The
sequences are applicable for UNITYplus and
UNITY
INOVA as well as UNITY and VXR-S
with a Sync Module.
Macros
The macro
mrev8
converts a S2PUL or FLIPFLOP data set for BR24. cylmrev converts a
data set for quadrature MREV8. All relevant parameters are preserved if the initial data set
is FLIPFLOP, BR24, CYLBR24, MREV8 or CYLMREV.
Parameters
pw
is the 90
o
degree pulse-length, in microseconds.
tau
is the interpulse delay, in microseconds, including
pw
. The MREV8 cycle is 12*
tau
long and is repeated
np/2
times to build up a FID.
trig='y'
for UNITY and VXR-S with a Sync Module. Otherwise
trig='n'
.
tauc
is the cycle time, in microseconds and is the actual dwell time for the FID. tauc is not
changed and is for information only.
mp_at
is the sum of all cycles, in microseconds, and is the true acquisition time.
mp_at
is not changed and is for information only.
sw=2e6
turns on the fast ADC without analog filters.
sw
does not determine the dwell time
(see
tauc
).
scalesw
is a scale factor that converts
sw=2e6
to the correctly scaled spectral width.
scalesw=(1.0/tauc*sw)*S
where
S
is the multiple-pulse scale factor for MREV8
(0.471 for ideal pulses).
rof1
and
rof2
(see
4.9 “FLIPFLOP - Pulse Width and Phase Transient Calibration,”
)
tau
2*tau
pw
acq
prep
0
3
2
1
0
3
2
1
d1
'np'/2 times
Figure 24. MREV8 Pulse Sequence