NMR Pre-Lab
INCLUDE THIS SHEET AS THE FIRST PAGE OF YOUR REPORT.
Before the 1st Day of Lab
Student's Name: ______________________________________________________________
Partner's Name: ______________________________________________________________
Watch the two videos on NMR & Pulsed NMR online.
Pre-lab Questions and Sign Off Sheet
It is your responsibility to discuss this lab with an instructor before your first day of your scheduled lab period. This signed sheet must be included as the first page of your report. Without it you will lose grade points. You should be prepared to discuss at least the following before you come to lab:
- What is nuclear magnetic resonance? What is resonating? What magnetic fields do we apply to our sample? What do these fields do? What is Larmor precession?
- Referring to Figure 6 of this lab manual, in what directions are the DC field, the modulating (60 Hz) field, and the RF field? What do these fields do? How do these fields relate to question 1? When you arrive in lab, examine how these fields are actually oriented in space.
- What are T1 and T2?
- How does pulsed NMR differ from the continuous wave NMR experiment?
- What is "free nuclear induction"?
- What is a "spin echo"?
Staff Signature ______________________________________________ Date ____________
Completed before the first day of lab? (circle) Yes / No
Mid-lab Questions and Sign Off Sheet
On day 3 of this lab, you should have successfully produced an H2O absorption resonance picture, with a calibrated frequency axis. What is the Lamor Frequency in Mhz? Show them to a GSI and get a signature.
Staff Signature ______________________________________________ Date ____________
Completed on the third day of lab? (circle) Yes / No
On day 7 of this lab, you should have successfully observed the spin echo on the scope. Show it to an instructor and ask for a signature.
Staff Signature ______________________________________________ Date ____________
Completed on the seventh day of lab? (circle) Yes / No
Other Questions to answer about this experiment as you go along
- Quantum Mechanics and E & M: Classical absorption and dispersion curves for light going through matter (covered in any 110 text). In the NMR lab you will encounter similar absorption and dispersion curves. Why should optical absorption and dispersion be so similar to NMR absorption and dispersion? [Hint: think of the relevant Hamiltonians!]
- E & M: The experiment relies on the induced voltage generated in a "pickup" coil surrounding your sample (in more than one way). Study the sample NMR head apparatus and understand how a magnetization induced in your sample can be "picked up" by the coil (which is basically just an RLC circuit). Does the frequency of the RF field affect the pickup coil's response?