NMR

NMR

1. Interactions

   • Dipole-Dipole
     • Direct
       • Through space
     • Indirect
       • Through bonds
   • Chemical shift
     • Isotropic
       • Mean average
     • Anisotropy
   • J coupling
   • Nuclear quadrupole coupling
     • Spin >1/2

2. Solid state

   • Magic angle spin
     • 54.75 degrees
     • Increases resolution
     • Cross polarization
       • Abundant to dilute
         • Enhance signal to noise
         • Reduce waiting time
       • Hartman-Hahn match
   • Single crystal
   • All anisotropic interactions
     • Broad peak
   • Not 1H NMR
     • Protons highly coupled
       • V. broad peals

3. 2D

   • Two time dimensions
     • Fourier transform
       • Frequency
     • Evolution period
     • Detection period
   • Plot
     • Contour lines
     • Diagonal peaks
     • Cross peaks
       • Coupling nuclei
   • Types
     • COSY
     • EXSY
     • Heteronuclear correlations
     • J-resolved

4. Basics

   • Zeeman splitting
     • Larmour frequency
     • Quadrupolar nuclei
       • Spin >1/2
         • Non-spherical
       • First order and second order splitting
         • Satellite
         • Central transition
     • Slope proportional to gyromagnetic ratio
   • Gyromagnetic ratio
     • Nuclear magnetic moment to nuclear spin
     • Magnetic field
       • Precession
         • Clockwise
         • Anticlockwise
       • Changes orientation of rotational axis
   • Liquid
     • Isotropic
     • Anisotropic
       • Orientation
       • Averaged
         • Fast molecular tumbling
       • Not spherical around nucleus

5. Relaxation

   • T1
     • Spin-lattice
       • Thermal equilibrium
     • Inversion recovery
       • First order rate process
   • T2
     • Spin-Spin
       • Loss of signal in xy
       • Field inhomogeneity
     • <T1
     • Spin echo
   • Chemical exchange
   • Nuclear Overhauser effect