Cyclopropane rings, characteristic bands

Raman spectra of saturated unsubstituted carbocycles exhibit not only bands which are typical of CH2 groups, but also bands representing characteristic in-phase vibrations of C-C bonds cyclopropane at 1188 cm (Fig. 4.1-10), cyclobutane at 1001 cm, cyclopentane at 886 cm, and cyclohexane at 802 cm. These vibrations are al.so found in many substituted ring systems C3 between 1220 and 1200 cm, C4 between 930 and 850 cm C5 between 810 and 800 cm , and Q between 800 and 700 cm . 

In order to describe group frequencies in the following sections, the structural unit which appears to be responsible for the band will be utilized. Such groups as CH3, CH2, CH, OH, or NH, or rings such as cyclopropane, benzene, etc., can be described as having characteristic group frequencies, as can also structural units such as the isopropyl and r-butyl groups. Finally, combinations of structural... 

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