Today we started our treatment of spectroscopy by looking at mass spectroscopy (MS). MS is used by organic chemists primarily as a first look at a compound's molecular weight by observing the molecular ion peak. It is also valuable as a method for determining structure by looking at fragmentation patterns -- a molecule is ionized by bombarding it with an electron beam and the resultant radical cation then fragments into smaller particles. These particles can be detected provided they have a charge. We saw a limited number of fragmentations for which you will be responsible, including alpha cleavages, dehydrations and McLafferty rearrangements.
A new problem set and key has been posted. Last year's exam has also been posted.
The picture is of Asa Larson. He studies the process of an electron recombining with a molecular ion (the reverse of the step that starts MS) in his work at the Royal Institute of Chemistry in Stockholm, Sweden.
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