1. Move the mouse to turn on the CRT screen. 2. At the login prompt type your login name and the password. Open VNMR software from the screen icon. Regardless of the operating mode the typical NMR experiment takes the following steps. A Prepare the sample and consideration in selecting a solvent. B. Log into the system as current user (Type your login name and password.), C. Insert the sample into the magnet, D. Enter the sample description, E. Select mode, set up (lock and shim) and run the experiment, F. Process and Print data, G. Remove test sample and return standard to the magnet obtain lock signal, and H. Sign out or use the Exit menu. 3. Open the menu to the lock screen. 4. Remove reference sample from the magnet by typing e or using the eject button. Place the sample in the holder with the collar up. (Look at the drawing on the leg of the magnet.) 5. Insert test sample A. Place sample tube into the collar and adjust the level relative to the pattern on the right leg of the magnet or in the depth gauge. Make certain the sample never goes below the bottom mark. B. Inset the sample and collar into the magnet and either use the lock menu button to insert the sample or the i command. 6. The sample should be spinning about 20 rpm. Normally it is not necessary to adjust the air flow but it can be adjusted by turning the valve counter-clock wise to increase the spin rate. Get help if there is a problem. No adjustment is normally required. 7. Turn lock off and use the lock screen to find the Z0 value for the solvent. If the lock is not found recall standard shim files and repeat. A. Type LK or open the lock screen. Make certain the sample is spinning. The green light on the NMR leg and the top of the lock screen should say "Spinning". Some users leave the instrument with the spin turned to zero. Adjust it to 20 rpm. B. Turn the lock off find the correct Z0 value. Do not attempt to adjust Z0 until the lock is off. C. Adjust Z0 with the value. Adjust Z0 so the lock signal displayed is a standing wave. You may need to increase the Lock Power (up to a value of 25) and/or the Lock Gain (up to a value of 30) or decrease depending on the instrument and sample. D. To lock the signal, turn the lock on. E. To obtain the Shim Screen go the the shim screen or type "S" plus a carriage return F. When adjusting any of the shimming parameters, the goal is to maximize the lock signal. You can tell this by looking at the two-horizontal bars on the screen. One is labeled "1X" and the other "5X". When the colored indicator is at it highest point in the bars, then you can go on and adjust the next parameter. Each parameter affects the lock signal. As a general rule you do not want to have the "1X" vertical bar pegged out. Reduced the Lgain if it is pegged. Start shimming your sample by adjusting Lpower, and Lgain. The lock phase will be constant, regardless of solvent. Exit the Z0 menu G. Do not adjust the Phase unless the console has been turned off. H. Go to the shim menu. I. Adjust the Z1C to the maximum intensity. J. Go back and readjust the Z1C parameter, then the Z2C, then the Z1C, then the Z2C, until the lock signal is maximized. K. Turn down the Lpower if the "1X" indicator is greater than 50%. L. Continue to ajust the Z1C, Z2C until you are confident the lock signal is maximized. Maximize the shim homogeneity by starting with the coarse adjustment and working clockwise. The range should between 60-80. It may be brought into this range by adjusting the gain and power adjustments. 9. To acquire data (Taking Spectra): A. Check parameters. For CDCl3: tn=1.75, nt=16 or use setup for the proper solvent and nuclei for standard 1H (CDCl3) parameters. B. Use the menu to begin acquisition or type GA. While instrument is collecting data you may enter text to identify the sample by typing "TEXT(`....')". Note you must use both parenthesis and single quote marks. To stop acquisition type /aa. C. Once the data is acquired, you may remove the sample from the instrument and insert the next sample or the reference. The instrument is always left with a reference in the probe. The spectrum will appear when processing is complete, or use the ds command to display the spectra. 10. To process the spectrum: A. To set TMS as the reference type sp = -20, dcr. Line up the cursor on the TMS peak. Then type ro, sp = -10. Adjust the vertical scale with vs. B. To phase spectrum there are several choices. a. First int, lt (lvl = 0), x10. This will display your integration and an enlarged spectrum. You may visually inspect the phase and adjust it with the rp and lp. b. Use aph to autophase if the spectrum is badly out of phase. c. Finally, you may type d2cr and place the cursors on the CDCl3 and TMS peaks. Then type set. Adjust the phase and type ds. 11. Once the spectra has been taken type wft aph f full (for Weighted Fourier Transform, AutoPhase, and Full Spectrum) A. Reference the spectra is automatic from the menu.. B. Type nl rl (for nearest line reference line). C. To see the whole spectrum type f full and a carriage return. 12. To print the spectrum: A. Setup by typing WP=9P SP.5P (for width plot and start plot) B. Integrate the spectrum: Type int cz (for integals and to cut prior value) To cut the spectrum select czto bring up the cursor, move the cursor to where you want to cut, and then press cz to cut the integration. Press cz again to bring back the rest of the integration. Move the cursor to the next place you want to cut and press cz. Move the cursor to the other side of the peak and press cz until you are done cutting the spectrum. C. Labeling Peaks: Press Menu to bring up the horizontal threshold cursor. Using the button for threshold move the horizontal cursor so that all the peaks you want labeled are at or above the threshold cursor. Type dpf (for Display Peak Frequencies) 13. The menu allows for automatic printing. There are a few macros that print the spectra and scale: PN1 or PN2. The former is a macro that gives the following commands PL, PLHEAD, PSCALE, PPF, PAGE. While PN2 is for the following: PL, PLHEAD, PSCALE, PAGE.
There is also software print from NMR SpecManager.
The following table is only for reference. Leads must not be removed or connected from probes.
1. Use a concentrated sample. 2. Change the parameter configuration setup values.
The following table shows the old values now being used to run carbon and the suggested values. Please try the suggested values. The suggested parameter setting are stored and can be recalled with: RTP(standard).
1. Resolves peak picking problems. 2. Carbonyl peaks at 200.4 and 155.7 are easily resolve without long acquisition times.. 3. Free up the Gemini 300 time in room 130.
