Rotations in polyatomics

Rotations in Diatomics 396 Rotations in Polyatomics 400 BIOSKETCH Stewart Novick 402 Spectroscopy of Rotational States 406 TOOLS OF THE TRADE Radio Astronomy 408... 

Another important mode of rotation in polyatomic molecules is internal modes of rotation. As an example, consider the rotation of a methyl group about the C-C bond axis in ethane. The rotation of the methyl group can be approximated as a free rotor about the < i angle as in the Particle-on-a-Ring model problem (see Section 3.1). From the moment of inertia of the methyl group, the energy of the internal rotational states can be obtained from Equation 3-6. 

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