Welcome to the NMR Lab.
All training is by appointment with Dr. Kababya or Dr. Balazs, 829-3748.
Each lesson is 45 minutes, with 1-2 lessons per week.
Training includes how to arrive with a sample and leave with a NMR spectrum.
The first lesson is a demo. The second lesson is hands-on. After completing your hands-on lesson, you may work independently to acquire 1H spectra on the DPX200. You may also receive, by request only, a password to work with the automated NMR (AVIII-400) spectrometer.
Shifi Kababya and Yael Balazs are available in the lab Sunday through Thursday (7:30 - 15:30) to answer short questions on-call or to schedule appointments for more involved assistance. Training is independent of any NMR workshops, courses, or conferences.
What to do:
- Before your first lesson, read the basic instructions.
- Bring a hardcopy of the instructions with you to your lessons.
- Attend an NMR workshop.
The Practical and Theoretical Exams
Instruction beyond acquiring a basic 1H spectrum on the DPX200 is contingent upon you demonstrating to the facility managers that you have grasped the first five parameters that apply to all instruments and NMR experiments: sfo1, d1, ns, td, dw.
This is done by completing the practical and theoretical "exams" detailed below - at any time that you feel ready, including your first day in the NMR lab. Before more one-on-one NMR will be taught to the new user (i.e. additional parameters and concepts), you are expected to show the facility managers that you have achieved a basic level of competence and vocabulary based on your first lessons.
Samples are located in Yael's sample box across from the AVIII-400.
- acquire a non-truncated FID (off-resonance)
- acquire an on-resonance FID
- obtain a spectrum with good shimming
- obtain a spectrum showing the 13C satellites
of the CH2 quartet of ethanol.
First review all the questions given below. When you have the answers, make an appointment with Yael or Shifi to check you answers. All the questions are answered in detail in the NMR workshop. The actual exam will be with the other facility manager. The exam consists of a few randomly asked questions related to the list below.
- What nuclear property is needed to see a NMR signal?
- What is the purpose of the NMR button “spin”?
- What does shimming do?
- Which shims should be used with or without sample spinning?
- How can you tell the difference between poor shimming and a real multiplet?
- What does “lock” do?
- Can you acquire a spectrum without lock?
- Do you want the sweep on or off while you acquire your FID?
- What happens to a solution NMR experiment without deuterated solvent?
- What does “200” stand for?
- What is the difference between the 200 and 500?
- When is the 200 better?
- When is the 500 better?
- What is the ppm scale?
- What is d1?
- What is T1?
- What does aq + d1 = 5 x T1 imply?
- How are the spectral width and digitization rate related?
- Which parameter increases the time that the detector is on?
- How can you recognize a peak that is on-resonance?
- Will an on- or off-resonance FID decay faster?
- Which parameter is changed to improve the signal-to-noise ratio?
- What is the difference between multiple-pulses and number of shots?
- How do you convert intensity vs. time to intensity vs. frequency?
- When do you use a Gaussian function in processing?
- When do you use an exponential function in processing?
- Why do different protons have different chemical shifts?
- What causes J-coupling?
- How can you distinguish between a doublet (J-coupling) and two singlets of equal intensity?
- What safety concerns are connected to working in a NMR lab?
- What are the scheduling rules?
- What are the lab policies?