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CH1012
NMR SPECTROSCOPY II
Nuclear Magnetic Resonance Spectroscopy
• NMR is a property
of atomic nuclei.
• Many atomic nuclei possess spin
angular momentum I which is quantised.
(quantised = discrete units, +1, +2 not 1.01…1.02)
angular momentum I which is quantised.
(quantised = discrete units, +1, +2 not 1.01…1.02)
• From physics we know that a spinning
charge generates a local magnetic field.
• A nucleus with spin therefore behaves much as a small
bar magnet.
S
+
N
• We will focus on 2 nuclei:
13C
and 1H both have spin
1/2 (I = 1/2)
13C 1.11% nat. abund. 1H 99.98% nat. abund.
