Things NOT to do With or Around an NMR Spectrometer
If You Want a Short Career in NMR Do The Following
I have been around students using nmr spectrometers for many years now and like to think that I've seen just about every goofy/dangerous thing but ...
The really dumb stuff is prefaced with "I can't believe that I have to say this".
Here's a list of stuff that I have seen that you should not do:
- Do not put your sample into the autosampler and program it and then, some time later, come back and take the samples out if they have not be run yet. If you must do so, PLEASE also cancel the samples in ICONNMR. Otherwise when the machine encounters an empty sample holder when it is expecting to find a sample it will choke on it. Remember, computers are dumb, dumb, dumb. They can't figure out what to do.
- Do not make the mistake of thinking that just because a sample in the autosampler carousel is past the sample injection point that it has already run. The only way to know if it has run is to look at the iconnmr display.
- Do not be helpful and clean the nmr tube depth gauge with acetone. The gauge is plastic and will dissolve in acetone
- Do not put a sample into the magnet and begin to take data when we are filling the magnets with cryogens. If you don't understand why you shouldn't do this then you should not be using the spectrometer.
- I can't believe that I have to say this. Do not put the spinner on upside down and then put sample and spinner into the magnet. There will be problems.
- Do not be helpful and try to fix a broken depth gauge ... there are tiny springs in the stop mechanism that will fly out if you try to take it apart, never to be found again.
- I can't believe that I have to say this. Do not put your sample into a depth gauge and then try to put the whole thing, gauge and all, into the magnet.
- Do not put little tape 'flags' with the name of your sample on your nmr tube. If the flag is left on the tube it will stick inside the magnet for sure (Murphy's Law).
- I can't believe that I have to say this. Do not force the tuning/matching rods to turn further than their maximum or minimum postions ... this will cause serious internal damage to the probe and render it immediately useless until repaired.
- I can't believe that I have to say this. Do not put the sample into the magnet unless the lift air is turned on. Again, you risk damaging the probe if you simply drop the sample into the magnet.
- Do not forget to shut off the lift air after you are finished with the machine.
- Do not overreach when inserting or removing a sample ... you might lose your balance and injure yourself or you might break an nmr tube with sample in it.
- Do not bring a magnetic substance near to the magnet ... after all it's a magnet and a very powerful one at that. Screwdrivers and wrenchs are death tools around an nmr magnet ... keep them away!
- I can't believe that I have to say this. Do not resort to fisticuffs to resolve disputes surrounding who has the right to use the machine. It's really not that important. Go get a coffee and read a book or something.
- If you think that the nmr software should do everything for you and that there's something wrong if it doesn't ... good luck to you. This is the same as thinking that a hammer should put the nails into the board for you without you doing anything. Learn how the software works.
- I can't believe that I have to say this. Do not pull on the autosampler carousel in order to rotate it and retrieve your sample!!! Ever.
- Do not fall into the trap of thinking of yourself as an expert ... you aren't and will probably make a fool of yourself at some point if you don't come to realize this. There are no experts in nmr spectroscopy except those who are Nobel laureates and most of them have passed away. 'nuff said.
- Do not start up the Xwin-nmr software in your lab and leave it running for a long time. We have only five floating node licenses which means that a maximum of five remote sessions of Xwin-nmr can run at one time. If you leave your copy running you might be denying someone else the chance to use their copy. If you are having problems because all of the licenses are currently being used why not try Kirk Marat's excellent software, Spinworks. You can get a copy for Windows by opening a 'My Computer' window and putting '\\chem4823' into the location bar. Spinworks is in the utilities folder.
- YOU are responsible for the shimming. If you cannot shim your sample try starting from scratch by reading in the standard shim file (type 'rsh' and select 'currentshim') before complaining to the laboratory manager. If you still cannot shim the sample satisfactorily then a) you don't know what you are doing (read the section on shimming) or b) there is a problem with the machine or c) your sample cannot be shimmed for some reason.
I think that I really shouldn't have to say any of this to anyone but experience shows that this is not so. Educate yourself about the spectrometer (via these pages and library books) and, please, use some common sense.