Specification

Available Experiments

The NMR instrument in teaching labs is run as a submission service. The following 1D and 2D experiments are available as routine experiments. In addition, non-standard experiments can be recorded if required. For example increased scans or variable temperature experiments.  Where specialist experiments are not available within teaching labs, samples will be transferred to other service instruments in the department.

1D Experiments

2D NMR experiments

Submission

Taught Undergraduates

Samples should be dissolved in the minimal amount of deuterated solvent in a sample vial and be filtered through cotton wool into a clean NMR tube. Please be careful with the tubes, they are expensive and can be reused many times. Please return any dirty or damaged tubes to the prep-room for washing and reuse.

Solvents available

• Deuterated chloroform (preferred)

• Deuterated water

• Other solvents may be available in exceptional circumstances, please discuss your requirements with the technical staff.

Computer submission

Samples should be labelled with one of the numbered tags and be placed in the appropriate pot on the bench opposite the prep room. The details for your sample and the experiments you require should be filled in on the google form accessed by the submission hub.

Your sample will be taken to be queued up on the spectrometer and will normally be as soon as possible.

Teaching Laboratory Based Project students

When projects are running in the lab (eg BSc and MChem miniprojects), we operate a prioritisation system for samples in order to ensure fast turn-around of results.

During the day only samples requesting a single 1D proton, phosphorous or fluorine experment will be submitted during the day in order to provide a rapid return of results. All other samples will be queued to run overnight.

If you would like multiple experiments on a sample (eg carbon, DEPT, COSY, HSQC), it is good practice to record and view the results for a short experiment (proton, phosphorous or fluorine) first and ensure that your sample is suitable for recording additional experiments in order to minimise wasted spectrometer time. All samples for project students will be retained until 4 pm on the following Tuesday and you should request additional experiments using the submission form. You should not generally prepare new samples for recording additional nuclei.

If the nature of your chemistry will require samples to be run immediately after they have been prepared (whether for short or long experiments), please liase with the technical staff as early as possible, and certainly in advance of any sample preparation. Wherever possible we attempt to assist with these requests.

Please discuss any NMR requirements with the demonstrators in the labs, the technical staff or your project supervisor for advice.

Accessing data

After you have submitted your spectra, you should find out the sample reference number for your sample. These are stored first by date, then by experiment number. The links below give access to the experiment numbers (York login required). The spreasheet has multiple sheets, the first is the pending queue (Form Responses) which are awaiting submission to the NMR spectrometer. The other sheets are labelled with the date when the experiments were run. You should find your sample and look at the experiment number to be able to find your sample.

After you have identified your sample number, you can then find the PDF file for your spectrum. NMR files are located in the NMR folder. and are then organised by date, then by experiment number.

To access the PDF file you will need to go into the /pdata/1/ folder of the experiment. The PDF file is named in the format email_yyyy-mm-dd_expno_1.pdf

Step by step instructions

NMR - Viewing Spectra (MS Word) ↓

Reprocessing spectra

In order to get the best use for NMR data, you will need to reprocess all NMR Spectra recorded after the first year. The department's preferred software is ACD/Spectrus which is available on all classroom and lab PCs and for home use. If you wish to use any other NMR Reprocessing software, you are free to do so, so long as the end results are comparible.

In order to reprocess NMRs, you will first need to download the whole experiment folder for your sample using an SFTP client.

Useful resources

NMR Solvent Impurities

Spectroscopic Methods in Organic Chemistry (Williams and Fleming)

NMR Frequencies

The Teaching Labs NMR spectrometer is a 7.04925 Tesla magnet operating at the following frequencies: