Molecular Biophysics

Molecular structure by NMR (I)

Today:

Magnetic properties of nuclei Chemical shift Fine structure

number symbol Electron configuration

Electrons/shell

Atomic weight

Magnetic properties /Misc.

1 1H2H (1p +1n)

1s1 1 1 75% of universe mass, spin ½ 2H: spin: 1

6 12C (6p+6n)13C (6p+7n)

1s22s22p2 2,4 12 13C: spin ½ (1%)

7 14N (7p+7n)15N (7p+8n)

1s22s22p3 2,5 14 14N spin 115N spin ½ (0.4%)

8 16O (8p+8n)17O (8p+9n)

1s22s22p4 2,6 16 17O: spin 5/2 (0.04%)

15 31P (15p+16n) 1s22s22p6

3s23p3

2,8,5 31 spin ½

16 32S(16p+16n)33S(16p+17n)

1s22s22p6

3s23p4

2,8,6 32 33S: spin 3/2 (0.75%)

Import atoms in biomolecules

1

4

3

2

3

2

number symbol gyromagnetic factor [107 rad s-1 T-1] (nat. abundance)

1 1H2H (1p +1n)

26.7522 (99.9%)

4.1066 (0.01%)

6 12C (6p+6n)13C (6p+7n)

---

6.7283 (1.07%)

7 14N (7p+7n)15N (7p+8n)

1.9338 (99.6%)

-2.7126 (0.4%)

8 16O (8p+8n)17O (8p+9n)

----

-3.6280 (0.04%)

15 31P (15p+16n) 10.8394 (100%)

16 32S(16p+16n)33S(16p+17n)

----

2.0557 (0.75%)

Import atoms in biomolecules