ABSTRACT
You should now be at least somewhat versed in the interpretation of mass spectra in terms of fragmentation reactions and how the products of these reactions (the ions) are used to reconstruct molecular structures. The chemistry of mass spectrometry has been presented to relate many of the fragmentation processes to one another and to the more familiar solution chemistry. When taken in this light, mass spectra can usually be interpreted by the individual chemist, so that the chemist does not have to rely on an experienced mass spectroscopist. We have assumed in our discussions, however, that (1) the spectrum of a compound can be obtained with little or no difficulty by conventional means, and (2) the compound fragments in a manner characteristic of its structure. In the more routine cases, with fairly large (>1 mg) amounts of a relatively volatile sample, spectra are obtained by introducing the material through a reservoir. Somewhat less volatile and smaller samples may be introduced through a direct insertion probe into the ion source itself. Many problems are encountered, however, that require special treatment, particularly when a material is very polar and does not have sufficient vapor pressure.
