NMR Operations for QE 300 (brief)
For more details about these directions see QE 300 operation (detailed).
Typographic Conventions:
- Special keys are written out, press the key shown, ie: <return> means to press the key that says "return".
- Most commands are entered as 2 letter commands. These commands are represented here as
bold caps in brackets ie [EJ]. They are entered without a <return>.
- Some sequences require holding the control key and pressing an additional key. [^W] means
hold the <control> key and press W.
- Additional comments are made in italics.
- A sequence of keystrokes or commands is separated by commas.
Safety:
- DO NOT ENTER KB 421 if you have a pacemaker or other metal implant.
- DO NOT place any magnetic material near the magnet.
- DO NOT drop small metal material in the room.
- DO NOT bring large metal objects into KB 421.
- Credit Cards, Computer Disketts, and ATM cards can be erased inside the yellow warning
rope.
- DO NOT work unsupervised
- Follow Directions and Ask questions. The NMR costs about $150,000, be careful
- Sign-in the logbook
Sample Preparation:
- Use the high-quality 8" NMR tubes
- Add Sample to the tube
- For liquid samples use a couple drops of sample in the NMR tube
- For solid samples add a couple microspatula tips
- Add an appropriate solvent to a height of 4 cm (Use the sample holder)
- Wipe the outside of the tube with a clean Kimwipe.
- DO NOT GET FINGERPRINTS INTO THE NMR.
Sample Loading:
- Eject the current sample from the NMR. [EJ]
- Remove the sample (DO NOT TOUCH THE SPINNER).
- Place the spinner on your sample tube and set the spinner height with the gauge.
- Wipe any fingerprints off of the NMR tube with a Kimwipe.
- Place the tube (WITH THE SPINNER) on the stack.
- Lower the sample into the the NMR. <return>
- Place the Plastic Cap on the top of the Stack.
- The Spin (top center of monitor) should read 15 or 16 (use AA to adjust).
Setup the Magnet For The New Sample
- Select the solvent for Deuterium Lock. [NS]
- Setup the Deuterium Lock. [LD]
- Set the Transmitter Gain. [T]
- 200 for CDCl3
- 125 for D-6 Acetone
- Toggle to the sweep display. [S]
- Center the peak by changing the offset. [O] (then use knob to adjust)
- Toggle to the meter display. [S]
- Set to Lock Fast Mode. [L] (press until "Lock Fast" is selected)
- Set the Gain. [G] (use knob to adjust signal to 70)
- Set to Lock Slow. [L] (press until "Lock Slow" is selected)
- Exit Lock Display. <return>
- Shim the Magnetic Field. Execute the Shim Macro. [XM], 64, <return>, Y, <return>
- Return to the Lock Display and reset the gain to 70. [LD], [G], (---)
Setup Computer for New Experiment
- Select the Current Nucleus. [CN]
- Set the Reciever Gain. [SG]
- Set the Number of Acquisitions (start with 8 for 1-H, 64 for 13-C). [NA]
- Set the Block Size (suggest 16k for 1-H, 32k for 13-C). [CB]
- Parameters for special pulse sequences (Optional)
- Select the Pulse Sequence. [EX]
- Setup the Decoupler.
- Select Frequency (ppm). [F2]
- Select Power (attenuation, start with 2800). [L1]
- Turn On and select modulation. [DN]
- #2 for broadband decoupling
- #4 for selective decoupling
- Changes to standard conditions (Optional)
- For optimum S/N;
- Determine T1, T2*, and spectral window.
- Set Recycle Delay to 0 sec. [D5]
- Set the aquisition time so D2 > 3 × T*2 . [CB]
- Set pulse to Ernst angle (From graph of acquisition time [AT] and T1). [P2].
- For optimum integration;
- Determine T1, T2*, and spectral window.
- Set Spectral Window to area of interest.
- Set Acquisition Time to 3 × T*2 by adjusting block size. [CB]
- Set tip angle to π/2, [P2], 90D,
- Set Recycle Delay [D5] so Acquisition Time [AT] is 5×T1
- Collect Data. [ZG]
- Save Data. [SA]
- Run Gossip on PC then [SE] to transfer file to PC.
Process the FID
- Baseline Correct FID. [BC]
- Optional processing to enhance FID.
- Zero Fill FID (improve digital resolution if needed). [ZF]
- Apodize FID with Line Broadening Factor. [LB] (optional, select one)
- Exponential Multipliction (improve S/N). [EM]
- Double Exponential Multiplication (improve resolution). [DM]
- Gaussian Multiplication (improve resolution). [GM]
- Fourier Transform FID. [FT]
Process the Spectrum
- Phase the Spectrum
- Autophase. [AP]
- Phase to previous settings. [PS]
- Set TMS to 0.0 ppm
- Zoom on TMS. [ZO]
- Select region with knob or cursor and arrow keys.
- Expand zoom region. [^E]
- Autoscale Y-Axis [^Y]
- Select the TMS Peak. [P]
- Reset the origin. [O], [0P], <return> (Offset, Zero, Peak)
- Return to full spectrum [^F]
- Plot the spectrum
- Place two pens in carriage
- Autoscale spectrum. [YS]
- Plot Spectrum. [PL]
- Label Spectrum. [LC]
- If finished advance to next page. [NP]
- Integrate (Not used for 13-C, unless followed intructions to optimize integration).
- Switch to Integration Display. [ID]
- Scale the Integration
- Increase. [I]
- Decrease. [D]
- Adjust the Integration
- Slope. <right> and adjust with knob
- Curvature. <up> and adjust with knob
- Plot Integral [P]
- Advance Plotter to next page. [NP]
Transfer Files using Gossip
- Run Gossip on PC
- From NMR use [SE] to send current data set to PC
- From PC use Gossip to download file by name
Cleanup
- Remove pens from plotter
- Switch to 1-H acquisition and default parameters. [CN], [P^D]
- Remove your sample. [EJ]
- Replace line shape sample. <return>
- Replace Plastic Cap.
- Change Solvent for lineshape sample (D-6 Acetone). [NS]
- Lock on line shape sample. [LD]
- Shim magnet. [XM], 64, <return>
- Turn Monitor Off.
- Turn Plotter Off.
- Signout Logbook.
This page is maintained by
Scott Van Bramer
Department of Chemistry
Widener University
Chester, PA 19013
Please send any comments, corrections, or suggestions to
svanbram@science.widener.edu.
This page has been accessed
times since 1/5 /96 .
Last Updated 1/5/96