NMR Usage

Access to instruments

Instruments are accessible to anyone who has been trained on their use by the Nuclear Magnetic Resonance (NMR) laboratory staff and who has a current account. No unauthorized training allowed.

We need to have a budget number (EFS string) on file to create your NMR account. If you do not have a budget number, applying for a Chemistry Department Sales Card Application & Temporary Stockroom Card will create one.

Each authorized user is given a six-letter login code and computer account for scheduling time on the instruments and for using the instruments. Please use a secure password. Do not let anyone else use your account: violators will lose access privileges for a one-week period.

After hours access via U-card

U-cards are activated on a weekly basis, usually on Thursday.

You must use a computer on the University network. Complete this U-card form. Only send the information once. If your U-card does not work, check with Letitia Yao in the Nuclear Magnetic Resonance laboratory.

If you are a newly-trained user of the Mass Spectrometry Laboratory or the X-Ray Crystallographic Laboratory, and you already have access to the Nuclear Magnetic Resonance laboratory, send an email to Letitia Yao, letitia@nmr.chem.umn.edu, to add your card number to the doors for those laboratories. Do not resubmit your card number.

General policies

No food or beverages near the spectrometers or workstations.

Do not leave your NMR tubes in the laboratory.

If a sample breaks in the magnet, contact the NMR lab staff immediately so the probe can be cleaned. This will minimize probe damage from corrosive solvents. Repairs for any damage to the probes resulting from user error are charged to the user group.

All users must abide by the scheduling restrictions posted in the lab.

Non-standard experiments (VT work, exotic nuclei) must be scheduled one week in advance with the NMR lab staff.

Read the manuals.

Sample preparation

Do not use chipped or cracked NMR tubes.

Use 7" or 8" tubes. Use 507PP (400 MHz) or 528PP (500 MHz) NMR tubes on all the instruments to prevent damage to the probes. The NMR lab does not provide solvents or other supplies for your use.

Standard shims for the Bruker instruments, 40 mm (0.55 mL). Shorter samples require additional time to shim. Longer samples waste solvent and dilute the concentration.

Variable temperature work

Separate training is required for variable temperature work.

For sample preparation, use no more than 0.45 mL of solvent.

Be aware of the temperature limitations on the probe you are using. If unsure, ask!!

Always use new 528 NMR tubes and the special VT spinner for VT work. Old tubes may be scratched and more likely to break.

For variable temperature work, you must schedule enough instrument time to bring the temperature back to room temperature when you are finished. On the AV-500, this is 300K; on the AM-400, this is 298K.

Use restrictions

AX-400: 1-hour limit during the daytime, 3-hours maximum during the nighttime

HD-500: 1-hour limit during the daytime, 4-hours maximum during the nighttime

AM-400, AV-500: Monday-Friday, 8 a.m. to 6 p.m., 6 slots per user can be reserved up to 24-hours in advance; Monday-Friday, 6 p.m. to 8 a.m., and weekends, unlimited slots

All spectrometers for nights and weekends: reserve 2 weeks in advance, holidays, weekend restrictions in effect.

Service work

Samples may be submitted to the NMR staff to run for you.