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Max T. Rogers NMR Tip of the Week Archives
Welcome
to the the Max T. Rogers Tip Archives. Each week we distribute
an e-mail alert detailing the latest status of our instrumentation.
The alert also includes various tips related to the facility, which
are designed to facilitate the use of the Varian spectrometers.
This
resource
page contains
all
the archived tips of the week, which have been sent since June
23, 2003. Scroll through the list below to find the desired tip.
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ARCHIVE YOUR DATA, YOUR DISSERTATION/PAPER DEPENDS ON IT!
Our NMR instruments aren't getting younger and unexpected data loss may occur.
Additionally, from time to time we will need to free up disk space by removing
some older files, which may include your data. We will warn everybody before
this occurs, but it's best to be prepared. To save on a ZIP disk (also
posted in room 240):
I. Login on a workstation in room 240 (the middle two) using Common Desktop
Environment
(CDE).
II. Insert your ZIP disk in the the ZIP drive. Wait for the ZIP window to appear
(about 30 sec).
III. Open the "Home folder" window. (Left click the "files" icon
in the bottom toolbar). All your datafiles will be shown on this window.
IV. Copying files:
a. To copy one file (ABC.fid for example):
Use the left mouse button to drag the "ABC.fid" file into the ZIP window.
To see the ABC.fid filename on the ZIP window: Select VIEW, then UPDATE.
b. To copy multiple files:
Keep the 'Control' button pressed down while selecting and dragging files.
V. Ending:
When you are finished select FILES, then EJECT in the ZIP window. Please logout
properly. To save data on your PC desktop or laptop or your MAC:
I. Open a browser window (e.g. Microsoft Internet Explorer).
II. In the address bar, type 'ftp://username@bes' and hit ENTER.
A new window will popup titled "Login as".
III. For the new window titled "Login as", in the "username" box,
ensure that it's the correct name (e.g. if you ftp://xyz1@bes, the username should
be 'xyz1'), if not change it. In the "Password" box, type the correct
password and click OK.
IV. The original browser window should now show your data folders for the desired
instrument.
Click and drag the files/folders to the desired folder on your hard drive.
V. To access another instrument, change the username in the address bar to the
desired instrument and hit ENTER. Continue using via Step III.
Your peak shape is dependent on the homogeneity of the NMR magnetic field.
By shimming, you are attempting to make the field homogeneous at your sample.
Many variables affect your peak shape. Those that are most important to
the user are:
1. amount of solvent: too little and you will have trouble shimming, particularly
with Z2. You should use at least 5 cm of solvent in the tube.
2. viscosity of solvent: the higher the viscosity, the broader your lines.
3. particulates in your sample: floating, undissolved matter in your sample
will have deleterious effects on your lineshape. If necessary, filter your
sample.
4. paramagnetic impurities: small particles of metals or other paramagnetic
materials will cause line broadening. This can be minimized by not using
metal spatulas to transfer your sample. Dissolved oxygen, which is paramagnetic,
also causes some line broadening. Degas your sample if you require the narrowest
lines possible.
5. the quality of the NMR tube: imperfections and unevenness in the NMR tube
glass will lead to a degradation in your lineshape. It is best to use NMR
tubes that are rated for the field you are using (e.g. on the VRX-500, use
a tube rated for 500 MHz or better)
For a guide on shimming and the affect of each shim set on lineshape (e.g.
poor Z1 causes symmetric broadening), see:
http://opie.nmr.siu.edu/manual/shim.html
Remember to start by typing ‘fixshims’. It is best to only vary
Z1 and Z2, then autoshim on Z1, Z2, and Z3. This should be good for most
samples.
To Save your own Shim Settings:
I. Shim as usual. See above for a basic procedure.
II. Type:
svs(‘filename’)
then hit RETURN
To Retrieve your Saved Shim Settings:
I. Type:
rts(‘filename’) su
VIEWING TWO SPECTRA SIMULTANEOUSLY:
Did you ever want to look at two spectra at the same time and determine
any differences (e.g. to see if changing the probe temp affects peak
location
or to look at the progress of a reaction by comparing to the starting
material)? It's easy with the addi program.
NOTE: Prior to using addi, you should be sure you don't have any valuable
unsaved spectra, parameters in exp5 because exp5 is the workspace used
for this program. If you have never used exp5, you should be fine.
To view two spectra at a time and see the difference between them:
I. In VNMR, type: jexp1 and hit Return
II. Acquire or load a saved file as usual and type: wft f and hit Return.
III. type: clradd and hit Return. This clears exp5, which is the default
add/sub buffer. IV. type: spadd and hit Return. This adds the current spectrum
to the
add/sub buffer (i.e. exp5).
V. type: jexp2 and hit Return. Acquire or load a saved file as usual and type:
wft f and hit Return.
VI. type: addi and hit Return. This will add the spectrum in exp2 to the add/sub
program.
You should now see three stacked spectra:
The bottom spectrum is from the current window (in this case it's from exp2);
the middle spectrum is the one from exp1 that you added to the add\sub buffer
using spadd;
the top spectrum is the sum of the two spectra (this is the default setting).
Interacting with Spectra:
On the bottom middle of the screen, you have two display terms; active: and
mode:.
active: designates which spectrum is currently selected. Any actions you take,
such as scaling size with the middle mouse, will change the active spectrum.
To select a different spectrum, click on [Select]. Note that active: will change
each time.
mode: designates the action taken to generate the result spectrum (top spectrum)
from the other spectra. The initial mode is add, which is the sum of the two
spectra. To switch to sub (subtraction of the spectra) or min (minimum points
between each spectra), just click on [sub] (note that mode is now sub), click
on [min] to get min, etc.
Printing the result (e.g. Difference between two spectra):
I. Once you have chosen the result you want, click [save].
II. type: jexp5 ds and hit Return. Now you have the result of either adding
two spectra or subtracting two spectra.
III. Print, expand, etc. in the usual manner.
(e.g. type: pl pscale page)
Did you ever want to stack multiple spectra and save them as an array (e.g.
the stacked view and plotting for DEPT) for printing and displaying? Well,
you’re in luck because it can be done. You can stack as many spectra
as you want either horizontally or vertically, view individual spectra,
and then save them as an array for later use.
TO PRINT STACKED SPECTRA: You will need to create an arrayed dataset, which
will allow you to view and print all stacked spectra.
Note: type what’s in the ‘’ and hit Return.
Important Commands for Arrayed Spectra:
ds(#) - where # is the spectrum number in the array. The first spectrum is
1, the second is 2, etc. (e.g. ds(1) to display first spectrum.
dssa - displays all spectra vertically
dssh - displays all spectra horizontally
dssl - displays the spectrum number(#) to be used with ds(#)
pl(‘all’) - print all stacked spectra
I. Load the spectra in exp1 and add them to an array: type ‘jexp1’ -
join experiment 1
II. Type ‘clradd’ - clear the add/sub buffer in exp5. This will
erase anything in exp5.
III. Click Main Menu => File and select the first desired spectrum and
click Load.
IV. Type ‘add’ - adds FID to add/sub buffer.
V. For adding all additional spectra, click File, select the desired spectrum,
click Load, and type ‘add('new')’.
VI. Join exp5 and create array parameters: type ‘jexp5’ - join
experiment 5.
VII. type ‘gain='y' ‘- turns off autogain, which is not allowed
in arrayed experiments.
VIII. type ‘d2=1,2,3’... - sets arrayed variable. Use same number
of variables as spectra. For example, if you want 10 spectra, type ‘d2=1,2,3,4,5,6,7,8,9,10’.
IX. Type ‘calcdim’ - calculates the array dimension.
X. Type ‘groupcopy('current','processed','acquisition')’ - updates
parameters.
XI. Type ‘ai’ - resets to absolute intensity mode.
XII. Type ‘wft dssa’ - Fourier Transform all FIDs and display
stacked spectra vertically. If you want horizontal stacks, type ‘dssh’.
XIII. Type ‘svf('your filename')’ to save the arrayed spectra.
You may need to adjust the phasing. If phasing is incorrect, type ‘ds(1)’ (this
displays the first spectrum), or click Interactive. Type ‘aph’.
To adjust the scale of each spectrum: type ‘ds(spectrum number)’ (where
spectrum number is an integer. For the first spectrum, spectrum number is
1: ds(1); for the second spectrum, spectrum number is 2: ds(2); etc.). Adjust
the scale as usual. To check, type dssa.
XIV. To print, use standard printing commands except replace pl with pl('all').
For example, pl(‘all’) pscale pltext page.
CREATING AN ARRAYED EXPERIMENT FOR A KINETICS RUN.
Last week I described how to create an ‘artificial’ array in
order to stack spectra. This week I will describe how to create a true arrayed
experiment. An arrayed experiment allows the user to run multiple experiments
in a single session with no need for changing parameters each time a value
needs modification. Why would you want to run an arrayed experiment? There
are many circumstances where an arrayed experiment is useful. Did you know
that the DEPT macro is an arrayed experiment? Or perhaps you wish to determine
a 90∞ pulse for a HMQC experiment or you would like to acquire spectra
of a compound at multiple temperatures or maybe you want to take a spectrum
of a reaction every 10 minutes and you don’t want to sit around for
3 hours. I will use the last example to set up an arrayed experiment for
a kinetics experiment.
Internal Standard: I will need an internal standard that does not interfere
with the kinetics of the reaction and that does not have peaks that overlap
with my starting material or product. Furthermore, I should use an internal
standard in roughly a one-to-one proton equivalent to the substrate (a proton
equivalent is equal to moles/# of protons). It is also important that the
internal standard be somewhat similar to the compounds being measured to
ensure that the T1s are not too dissimilar.
Remember those T1s: If I do not allow for complete relaxation between pulses,
I will not get accurate integration and hence incorrect data. T1s for aromatic
and alkene protons can be longer than for alkyl protons. As a general rule,
a delay of at least 30 seconds between scans should be enough for complete
relaxation. If waiting 30 seconds between scans is not feasible, then I
would use the Ernst command, which will calculate the appropriate pulse width
based on a given pw90, at, d1, and T1. A good value for the T1 for Ernst
would be 30 seconds; thus, I would type ernst(30).
Instructions for Kinetics Experiments Performed in NMR Probe: Type text in ‘’ and
hit Return
There are two possibilities for running a simple array: using a macro or
using command line execution.
USING THE ARRAY MACRO: This will allow you to array parameters with set intervals
between scans.
I. Lock and shim on your sample or a blank sample with the appropriate solvent.
The second option is for when the reaction you want to monitor occurs at
room temperature or lower.
II. Take a quick scan (nt=1) to ensure proper shimming.
III. Type ‘ernst(30)’. Set nt=8 or to another value which will
be repeated in IVc. Type ‘su time’. Note the time, you will need
this.
IV. Set VT controller to desired temperature. Type ‘temp=# su’,
where # is your desired temperature in ∞C. Most instruments, except
for the VXR-300, which can be set to 100 ∞C, have a temperature limit
of between 0 and 50 ∞C. If you need to do temperatures outside of this
range, contact us at ext. 792. REMEMBER: DO NOT EXCEED THE BOILING POINT
OF YOUR SOLVENT! Allow the temperature to equilibrate prior to beginning
your kinetics array. You will need to shim at the temperature of your kinetics
run to ensure the best results.
V. Type gain=’n’. If this doesn’t work, type ‘gain=30’.
Autogain is not allowed for arrayed experiments.
VI. Setup the arrayed experiment:
a. Type ‘array’
b. Parameter to be arrayed: ‘pad’
i. This is the preacquisition delay which will set the interval between successive
scans.
c. Number of increments:
i. This is the total number of spectra or data points you want. If I want to
monitor a reaction every 10 minutes for 3 hours, I would need 18, so I type ‘18’.
d. Enter Starting Value:
i. This is the time between each individual data point (a data point consists
of 8 scans) or spectrum. To calculate this value, take the time in seconds you
want between spectra and subtract the time determined in step III. Thus, for
an example, I want to take spectra at 10 minute intervals, which is every 600
seconds. Step III gave me a value of 16 seconds; therefore, my pad should be
600 – 16 or 584 seconds. I type ‘584’.
e. Enter Array increment:
i. Type ‘0’. This sets the increment to zero, which means the preacquisition
delay will always stay the same. If you typed 1, the pad would increase by 1
second each successive spectrum.
VII. Run the experiment:
a. Insert your sample. Type ‘i’ and ‘go’. You won’t
be allowed to lock your sample as it is already acquiring. By locking and shimming
your sample or a blank prior to the arrayed experiment, you have set Z0 where
it will lock. The instrument should lock after a short period. At this time you
can shim to get the best possible spectrum. The first scan will occur after the
pad you set. You can shim throughout the experiment if you desire. It’s
a good idea to check the timing between each data acquisition using a stopwatch.
USING COMMAND LINE EXECUTION FOR AN ARRAY:
This allows you to have differing values between each data point or spectrum.
I. Follow steps I-V above.
II. Type, for example, when you want to take a spectrum every 10 minutes (see
VI. d. above) ‘pad=584,584,584,584,584,584’ to take six spectra with
about 10 minutes between each data point. Each number represents an experiment
with the preacquisition delay (pad) in seconds set for that number. If I wanted
to take 5 measurements at 10 minutes, 15 minutes, 17 minutes, 20 minutes, and
40 minutes, (assuming the actual acquisition takes 16 seconds, see VI. d.) I
would type ‘pad=584,284,104,174,1184’. Remember that the pad is the
time between each data point.
III. Run the experiment:
a. Insert your sample. Type ‘i’ and ‘go’. You won’t
be allowed to lock your sample as it is already acquiring. By locking and shimming
your sample or a blank prior to the arrayed experiment, you have set Z0 where
it will lock. The instrument should lock after a short period. At this time you
can shim to get the best possible spectrum. The first scan will occur after the
pad you set. You can shim throughout the experiment if you desire.
Save your arrayed experiment as you would a normal experiment (i.e. svf(‘filename’)).
Important Commands for Arrayed Spectra:
ds(#) - displays spectrum #, where # is the spectrum number in the array. The
first spectrum is 1, the second is 2, etc. (e.g. ds(1) to display first spectrum).
dssa - displays all spectra vertically
dssh - displays all spectra horizontally
dssl - displays the spectrum number(#) to be used with ds(#)
pl(‘all’) - print all stacked spectra
FIX THOSE ANNOYING DISPLAY COLORS IN VNMR.
The odd colors for your VNMR interface are usually a result of having too
many windows/applications open. Since VNMR is generally the last to be
opened, it is given the last dregs of color available, which turn out to
be pretty awful. You should close all unnecessary applications prior to
running VNMR.
TO FIX THE DISPLAY COLORS OF VNMR:
I. After logging-in to the session and prior to running VNMR, close all
windows that pop up (e.g. Netscape, Solaris Registration, Terminals, etc.).
a. If you have the Solaris Registration window open every time you log-in,
you can disable it by clicking More Information=>Never Register=>Never
Register.
II. Click on the VNMR icon. The colors should be fine. If not or if you want
your own colors, do the following:
a. Type ‘color’ and hit Return. A color palette will appear.
b. Click on the button for the item you wish to change the color (e.g. background,
spectrum, etc.) and then click on the desired color.
c. When completed, enter a filename for the name color scheme and click save.
If you want this new scheme to be the default, save the file as DEFAULT.
RESET THE ACQUISITION COMPUTER WHEN THE SYSTEM IS UNRESPONSIVE.
If Console is unresponsive to Commands, follow the procedure below:
1. With the right mouse button, click once on the Solaris desktop background
to reveal a menu. Click on Programs or Tools, then over to select Terminal… A
Terminal window will pop-up.
2. In the Terminal window, type ‘su acqproc’ and hit Return.
You will get a message indicating that acqproc is being ‘killed’.
Also, in the ACQUISITION STATUS window in VNMR, STATUS should now read “inactive”.
3. Proceed to the NMR console, which is the big grayish box. See below for
location of reset button for various instruments.
4. Push the reset button. See location information at end of document to
find reset button.
5. After pressing the reset button, wait for at least 60 seconds.
6. In the terminal window type ‘su acqproc’ and hit Return. This
will take a few moments. Look at the ACQUISITION STATUS window in VNMR. Wait
for STATUS to read “idle”.
7. In the VNMR command line (i.e. where you usually type e), type ‘su’ and
hit Return. The NMR should now be ready for use. Repeat if this does not
restore system.
8. For VXR-500: If the proceeding procedure did not work, repeat the above
procedure, but instead of pushing the reset button, flip the switch directly
below the ‘reset button’ to off. Wait about 20 seconds and switch
it to ‘on’. Follow Steps 4-6.
LOCATION OF RESET BUTTON FOR EACH INSTRUMENT:
Anubis: VXR-500 (subbasement)
Reset button is in the big grayish box to the right of the computer. Open
the middle door and look for a button on the left with a hand written label “reset
button”.
Ra: Inova-300 (subbasement)
Reset button is in the grey box to the left of the computer, open the left
door and look for the hand written blue arrows to the middle left. The red
button below 'reset' at the far left where the blue arrows point is the button.
Hathor: G-300 (5th floor)
Open the door of the box to the right of the computer. Look for the switch
with the hand-written word, 'reset'.
Maat: VXR-300 (2nd floor)
Reset button is on the front right side of the box to the right of the computer.
Look for an arrow pointing toward a black button.
Khufu: Inova-300 (2nd floor)
Open the left door of the box on the wall with windows. Look at the middle
left and just above the blue plug. The small white button above the letters
RST is the button.
MODIFY ‘DPF’ TO GET MORE/LESS PEAKS PICKED!
Have you ever set your threshold below a set of peaks, typed ‘dpf’,
and only got a few of the peaks to be picked? It’s happened to me on
a couple of times. Well, that doesn’t have to happen. The default noise
level filter (noise_mult) is 3, which will give only a certain fraction of
the peaks. Try ‘dpf(1)’ or even ‘dpf(0)’. These will
give you more peaks. If you want less, try ‘dpf(5)’. How about
the pesky negative peaks that you don’t want? Don’t pick them
by typing ‘dpf(‘pos’)’ to pick positive peaks only.
Below is a list of what you can do with dpf.
EXAMPLES OF DPF USAGE: First set the yellow threshold line below the desired
peaks.
Important: Remember to refresh the VNMR screen before entering a new dpf
command or you will see two sets of peak labels. Typing ‘ds’ or
clicking Interactive will refresh the screen.
Type ‘dpf(#)’, where # is a number below 3 to increase number
of peaks picked.
Type ‘dpf(#)’, where # is a number above 3 to decrease number
of peaks picked.
Type ‘dpf(‘pos’)’ to pick positive peaks only. You
can include the # argument to change number of positive peaks picked: e.g.
type ‘dpf(‘pos’,1)’.
Type ‘dpf(‘top’)’ to place the peak labels at the
top of the page.
Type ‘dpf(‘leader’, #), where # is a number in mm for the
labels to be placed above the peak. Default is 20 mm. Type, for example, ‘dpf(‘leader’,30)’ to
move the peak labels up.
Combine several to make your ideal peak label:
For example: dpf(‘pos’,0,’top’) will give all positive
peaks below threshold with labels at the top of the spectrum.
Or
dpf(‘pos’,5,’leader’,10) will give selected positive
peaks above the threshold with the peak labels on 10mm leaders.
TRY THE REGION COMMAND FOR QUICK INTEGRALS!
Have you ever been in a rush and didn’t have the time to mark off your
integral regions? Well, there is a Varian cure: the ‘region’ command
breaks up a spectrum into integral regions. I’ve tried it and it’s
not so bad, especially for quick spectra. Give it a try.
To automatically break the integrals into specific regions:
I. Click Part Integral.
II. Type ‘region’. This will break the integral into peak regions.
III. If you need tighter integrals to get more peaks, type ‘region(10,1)’.
The numbers in the parenthesis describe the tail length and relative number
of integrals. The default values are sw/10 and 12, respectively.
Other settings for the ‘region’ command are:
Full syntax: region(‘tail_length, relative_number, threshold, number_points,
tail_size)
tail_length: length in Hz that is added to the beginning and end of each
integral region. The default value is sw/10.
relative_number: number that, in combination with other factors, governs
the relative number of regions to be found. The default value is 12. A value
of 1 would give more regions; a value of 100 would give fewer regions.
threshold: a sensitivity factor used to decide if a data point is large enough,
relative to the noise level, to qualify as part of a peak. The default value
is 0.6.
number_points: governs the number of successive data points, normally from
7 to 40 points, that must qualify as part of a peak.
tail_size: a number that governs whether two spectral areas that contain
peaks are close enough to be regarded as a single region.
Examples: region – uses default values.
region(10,1) – sets the tail length to 10 Hz and the relative number to
1. This gives more peaks.
region(-1,0,0,2) – sets tail_length, relative_number, and threshold to
their default values. Sets number_points to 2. This would be used for spectra
with large spectral widths.
IV. After the region command is used, reference your integrals as usual.
USE ‘GETTEXT’ TO ADD TEXT TO YOUR PLOTS!
Currently, most of us add text to the spectrum by typing, “text(‘name
of spectrum\\solvent instrument\\date etc.’)”, where the \\ signify
a new line. There is an easier way to enter and modify text. You just need
to type: gettext. This will execute a simple text editor. You will be able
to see and edit text that is already there. Furthermore, you will be able
to add text using the Return key to start a new line. Try it, you’ll
like it!
TO USE THE WINDOW BASED TEXT INPUT: Type: gettext and hit Return. It may
take a few seconds for the grey window to pop-up.
You may get the following error message,’The OpenWindows environment may
no longer support…’. This is not a problem, simply check the box
next to the line,’Check here to disable this message,” and click
OK; it will not appear again.
1. Add text to the large text box and hit Return when you want to start a new
line. When completed, Click OK and your text are ready for plotting.
2. If you need to edit your text, type, gettext, and edit as you would in Word.
Click OK when completed.
3. Plotting is done as always; the pltext command. To plot it in the top right
corner, use pltext(150,150) in your plot statement (e.g. pl pscale pll pltext(150,150)
page).
Tuning the VXR-500. General Considerations:
1. Be sure that you setup the correct experiment (e.g. Setup=>C13,CDCl3
for carbon) and type ‘su’ after setup.
2. Be sure to carefully follow the instructions on the probe.
3. Do NOT force the tuning rods. They are FRAGILE. If you feel resistance
when turning the rod, you probably have reached the end and should turn the
rod in the opposite direction.
4. Always start tuning by turning the shorter rod (Red for Proton. Gold for
Carbon).
5. In general, you need only turn the shorter of the two rods for either
Proton or Carbon.
6. If you need to turn both rods, start by turning the shorter one until
you get a minimum on the meter. Then,…
a. Turn the longer one (Blue for proton. Black for Carbon) in a direction
opposite to what you turned the short rod. Turn the long one to the minimum
and continue turning in the same direction until the meter reading goes up
a bit (5 with the lower knob set to 60).
b. Now turn the short rod to minimize the meter reading and continue turning
in the same direction until the meter reading goes up a bit.
c. Return to the long rod and turn to minimize. Turn past the minimum as
before.
d. Repeat for both the short and long rod until the meter reading is minimized.
e. If this process does not lead to a minimum, try reversing the directions
you were turning the rods.
Calibrate or check actual temperature using tempcal command:
The temperature that is displayed in the Acquisition window
is generally not completely accurate. This can be caused by many factors,
including fluctuations in VT gas flow and inaccuracy in the thermocouple.
If you require exact temperature measurement for kinetics or for other reasons,
you can use the chemical shift temperature dependence of either ethylene
glycol or methanol to accurately calculate the actual probe temperature.
The facility has the appropriate samples to perform a temperature calibration.
For experiments with multiple temperatures, you should create a calibration
curve. The calibration curve can be used for more than a single run.
Procedure for Temperature Calibration:
I. Insert your sample. Lock and shim as usual.
II. Eject your sample and insert the calibration standard. Make sure that the
calibration standard is centered properly (i.e. the solvent should be centered
about the two white lines in the gauge).
a. The sealed samples are located in B-8. Use the ethylene glycol sample for
high-temperature calibration or methanol for low-temperature calibration.
b. Note: these samples do not contain deuterated solvent. Do not attempt to lock
or shim. The shimming you did for your sample will be sufficient.
III. Enter your desired temperature. For example, I might type ‘temp=40
su’ to set the temp to 40 degrees Celsius.
IV. Allow sufficient time for the probe and sample temperature to equilibrate
(at least 10 minutes).
V. Acquire a 1H spectrum (nt=1). Place the two cursors on top of the peaks.
VI. Type ‘tempcal(‘e’)’ for ethylene glycol or ‘tempcal(‘m’)’ for
methanol.
VII. After hitting Return, the calculated temperature will be displayed above
the VNMR command line.
VIII. Repeat for all desired temperatures.
Use autoshim to fix those funny peak shapes (can require several
minutes).
I. Insert, lock, and shim in the usual manner.
II. Click on auto to the right of SHIM:.
III. Choose L>M and Z1,Z2,Z3.
IV. Click Start. The button will change to Stop. The autoshimming will take
several minutes. Autoshimming will be complete when the button is Start again.
V. Close the Acquisition window and acquire a spectrum.
VI. If you are satisfied with the shimming, save them by typing svs(‘filename’).
VII. To retrieve them for later use, type rts(‘filename’) su.
Print an expansion on your full spectrum plot
using inset command.
To Print an Expanded Region (inset) with your Spectrum:
I. Process your spectrum as usual and type pl pscale pir pltext. DO NOT type
page. The page command sends the job to the printer. You want to hold this
job until you add your inset(s).
II. Put the cursors around the region for which you wish to print an expansion.
III. Type inset. The expanded view will appear on the screen. This view is
now interactive and can be manipulated like usual. The full spectrum is no
longer interactive.
a. Use the left mouse button to set the horizontal position.
b. Use the middle mouse button to set height.
c. Use the right mouse button to set size.
d. Use the vp command to set vertical position (e.g. type vp=40 to set the
inset at 40 mm)
e. If you expand the inset and wish to reposition the new expansion, click
sc wc and move as described before.
IV. To print the inset: type pl pscale pir etc. If you would like another
inset, repeat the process described above ensuring that you type pl pscale
pir after each inset.
V. When completed, type page.
VI. To reset the spectrum to the full page, type vp=12 f full.
Last Updated:
February 17, 2009
- WebMaster
URL: http://www2.chemistry.msu.edu/facilities/nmr/TipOweek.html
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