Origin of important fragment ion peaks:
Problem:
The mass spectrum of hexane is given below. Explain the origin of important fragment ion peaks observed in the spectrum.
Answer:
The molecular ion peak is observed at m/z = 86 and the prominent fragment ions are at m/z = 71, 57, 43 and 29. A little observation reveals that these fragment ions differ by a m/z of 14 units. This indicates that the different fragments differ by -CH2 - units. Accordingly, the possible fragmentation pattern leading to the observed peaks can be depicted as:
