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PE: Hydration, enthalpy and entropy. Intermediate structures Between Phases. 31 P Solid State NMR of lipid assemblies. Breath, anisotropy and isotropic chemical shifts. Solution Vs Solid State NMR. Fast isotropic tumbling. Slow to no molecular reorientation. Chemical shift powder patterns
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31P Solid State NMR of lipid assemblies Breath, anisotropy and isotropic chemical shifts
Solution Vs Solid State NMR Fast isotropic tumbling Slow to no molecular reorientation • Chemical shift powder patterns • broad lines • dipolar broadening • quadrupolar broadening • Isotropic chemical shifts • narrow lines • J couplings 2H NMR - quadrupole nuclei 31P NMR- S=1/2 nuclei
Magnetic Anisotropic Interactions Chemical shielding/chemical shift
Chemical Shift Dependence Upon Orientation Integrate over all space for a “powder” MLVs and GUVs act as powders. They are large enough to tumble slowly enough NOT to average the CSA and 2H quad interaction
Restricted motions • mixtures of different lipids • mixtures of different phases • exchange rates Dry powder
Exchange Between Two Sites: Effects on NMR Lineshapes Two states: A and B
