1H Homonuclear Decoupling on lutz and burger
Acquire 1H
NMR spectrum as normal. see acquisition and
processing of proton spectra
Enter the following commands:
homo='y'
dmm='c'
dpwr=xx
(This command sets the decoupler power. Use between -15 and
15, start with 2. If you check the spectrum and decoupling is incomplete, raise
the power.)
dm='y'
Click the left cursor on
the peak which you wish to irradiate. (If you have two cursors, enter
ds
which should reset the cursor(s). Then just click the left mouse button to get
the correct cursor.)
Type the following:
sd
The sd command sets the decoupler
frequency (dof) to the cursor position.
Acquire the spectrum. If
you have done everything correctly, a sharp signal with variable phase will
appear at the position that you irradiated.
If you need more or less
irradiation intensity change the dpwr parameter.
If you wish to decouple several
peaks you should consider setting up an array of dof values (decoupler positions),
one value for each irradiation position. If you have an array of dof values
the spectrometer will collect a series of spectra with decoupling at each dof
value in your dof array.
Obtain a routine H1 spectrum
and then use the cursor and sd to set the decoupler frequency as described above.
Write down the dof (decoupler frequency) values for each desired decoupling
position. Create the dof array by entering the following:
array='dof'
dof=(value1,value2,value3,etc.)
Begin acquisition by entering:
go
A spectrum will be obtained
for each value of the dof array. Save and process the spectrum in the usual
way. After processing individual spectra in the array can be viewed by entering:
ds(arrayvalue)
where arrayvalue is any index
value for the dof array (ie. 1,2,3,...,total number of decoupling frequencies).