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1D HOE difference spectroscopy

1H{19F}
Heteronuclear Overhauser Effect

    new expno
  1. new
    1. start a new experiment
    2. update the expno
    3. choose experiment: hoe_HF_1D

  2. standard 1H NMR
    Change the pulse program to zg
    • (type: pulprog zg)
    Acquire a spectrum as usual:
    • sign the log-book
    • lock
    • shim
    • rga
    • zg
    • proc
    Tailor the standard parameters:
    • td, sw, sfo1 (and optional/optimal: p1, d1)

  3. determine the offset for on-resonance irradiation
    type: sr o1
    (that is the letter o and the number 1)
    put the cursor on the peak to irradiate and WRITE DOWN the value in Hz
    recalibrate the spectrum (or for an approximate calibration, type: sr 0)

  4. the HOE experiment
    Increase the experiment number (expno "n"), type: iexpno
    (this is equivalent to choosing "Use current params" in the "New" window)

  5. update parameters
    1. click on AcquPars, or type: ased
    2. Change the pulse program to the 1D HOE sequence:
      type: pulprog hoehf_Marks.1
    3. ns 16
    4. ds 4
    5. o2p, enter the chemical shift for 19F in ppm

  6. set up the reference experiment
    Increase the experiment number (expno "n+1"), type: iexpno
    turn off the power level (PL) for the 19F pulses in the acquisition parameters (AcquPars, ased) by completely attenuating the amplifier, type: pl2 120 dB

  7. acquire both experiments ("n" and "n+1")
    1. Return to the first expno, type: re "n"
    2. check the experimental time for two experiments (type: multiexpt)
    3. Run two experiments, type: multizg
    interactive multizg window

    OPTIONAL: for a large number of shots, you can use the "multicyc"command to cycle back and forth between the two experiments
    for example, if you want 32 shots, use ns 16 with 2 cycles;
    if you want 256 shots, use ns 16 with 16 cycles
    **If you need to stop the experiment early, use "multihalt" to finish the current cycle and save the results.

  8. process
    1. Process the first experiment as usual
    2. To process the second experiment with the exact same parameters:
      type: "multiefp"
      A window will ask for (and display by default) the current experiment number ("n"), click: enter
      A second window will ask for how many experiments to process,
      choose 2 ("n" plus "n+1")
      interactive multiefp window

  9. create a difference spectrum
    1. Enter multiple display mode .md
    2. Add the second (reference) experiment, type: re "n+1"
    3. Highlight the green triangle to get the difference spectrum -
      you can use the floppy disk icon to save the difference spectrum in a different process number .md tool bar

Report problems and bugs to Yael or Shifi - 3748