Seeing Molecules Spectroscopy Revisited

You may want to get yourself a copy of Organic Chemistry I For Dummies by Arthur Winter (Wiley). It has some detailed sections on the theory behind instrumentation and exactly how it works. 

In principle, you can determine the complete structure of an organic molecule from just the IR, NMR, or mass spectrum of a compound. However, the process of determination can be very tedious. Organic chemists use all the data available when attempting to determine the structure of a compound. 

For example, they gather some information from each of the spectra they have available and combine this data to produce a structure consistent with all the available data. When looking at a compound such as CjpH2oO, they may look at the IR to determine whether the oxygen atom is part of a carbonyl group, an alcohol group, or some other group. Then they may look at the NMR spectrum to get some idea about the carbon backbone. 

Later in this book you can see the specific functional groups and explore other features of the spectra that are characteristic of the group. 

The methods in this chapter apply to the common types of organic compounds. Unusual compounds have their own characteristic behavior. The behavior of these unusual compounds normally isn t relevant until advanced courses in organic chemistry. 

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