Molecular Biophysics

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Molecular Biophysics
Molecular structure by NMR (I)
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• Today
• Magnetic properties of nuclei
• Chemical shift
• Fine structure

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Import atoms in biomolecules
number symbol Electron configuration Electrons/shell Atomic weight Magnetic properties /Misc.
1 1H 2H (1p 1n) 1s1 1 1 75 of universe mass, spin ½ 2H spin 1
6 12C (6p6n) 13C (6p7n) 1s22s22p2 2,4 12 13C spin ½ (1)
7 14N (7p7n) 15N (7p8n) 1s22s22p3 2,5 14 14N spin 1 15N spin ½ (0.4)
8 16O (8p8n) 17O (8p9n) 1s22s22p4 2,6 16 17O spin 5/2 (0.04)
15 31P (15p16n) 1s22s22p6 3s23p3 2,8,5 31 spin ½
16 32S(16p16n) 33S(16p17n) 1s22s22p6 3s23p4 2,8,6 32 33S spin 3/2 (0.75)
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Import atoms in biomolecules
number symbol gyromagnetic factor 107 rad s-1 T-1 (nat. abundance)
1 1H 2H (1p 1n) 26.7522 (99.9) 4.1066 (0.01)
6 12C (6p6n) 13C (6p7n) --- 6.7283 (1.07)
7 14N (7p7n) 15N (7p8n) 1.9338 (99.6) -2.7126 (0.4)
8 16O (8p8n) 17O (8p9n) ---- -3.6280 (0.04)
15 31P (15p16n) 10.8394 (100)
16 32S(16p16n) 33S(16p17n) ---- 2.0557 (0.75)