NMR spectroscopy nuclear magnetic resonance nuclei nuclear spin

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NMR spectroscopy nuclear magnetic resonance nuclei - nuclear spin quantum number I = 0,

NMR spectroscopy nuclear magnetic resonance nuclei - nuclear spin quantum number I = 0, ½ , 1, … 1 H 13 C 14 N spin states m = +½ m = -½ E Ho h E = H = h resonance 2 = radio frequency magnetic field Ho H = Ho + Hlocal

Hlocal He due to e- in vicinity Hh due to 1 H in vicinity

Hlocal He due to e- in vicinity Hh due to 1 H in vicinity

Hloc He due to e- in vicinity h (H + H ) = h

Hloc He due to e- in vicinity h (H + H ) = h E = 2 o e e- in motion near 1 H create small magnetic field deshielded shield 1 H from Ho TMS - s x 106 = o = chemical shift H downfield 10 ppm o upfield 0 ppm

deshielded c Ho downfield 10 ppm 5 H b a 2 H shielded 3

deshielded c Ho downfield 10 ppm 5 H b a 2 H shielded 3 H upfield 0 ppm c b a

C 4 H 10 O a signals b b a CH 3 CH 2

C 4 H 10 O a signals b b a CH 3 CH 2 O CH 2 CH 3 a c b d CH 3 O CH 2 CH 3 a b c a c d d e CH 3 CH 2 OH e CH 3 CH CH 2 CH 3 OH b amplitude a b 6 4 a b c d 3 2 2 3 a b c d e 3 2 2 2 1 3 1 1 2 3

tert-butyl methyl ether 2, 2 -dimethylpropanol b c b a b c b c

tert-butyl methyl ether 2, 2 -dimethylpropanol b c b a b c b c a b a a

a a b c c b c d

a a b c c b c d

Hlocal chemical shift He Hh spin coupling due to e- in vicinity due to

Hlocal chemical shift He Hh spin coupling due to e- in vicinity due to 1 H in vicinity magnetic fields will align with Ho n+1 lines 3 bonds apart doublet quartet

C 4 H 10 O a b b b a CH 3 CH 2

C 4 H 10 O a b b b a CH 3 CH 2 O CH 2 CH 3 a b c a d CH 3 O CH 2 CH 3 a b c d e CH 3 CH 2 OH a c d e CH 3 CH CH 2 CH 3 OH b a e b c d b d c a e

C 2 H 6 O a a CH 3 O CH 3 c b

C 2 H 6 O a a CH 3 O CH 3 c b a a CH 3 CH 2 OH a c a b c b

3 a C 4 H 8 O 2 b 3 c d 2 a

3 a C 4 H 8 O 2 b 3 c d 2 a singlet d c b a c doublet c a singlet b heptet triplet quartet c b quartet triplet b c singlet a

a benzene a phenol b c d a

a benzene a phenol b c d a

d c b a propylamine a singlet a b triplet c hextet d triplet

d c b a propylamine a singlet a b triplet c hextet d triplet d b c