Rotational Energy Equations for the Symmetric Rotor

VroRATIONAI ROTATIONAL ENERGY EQUATIONS FOR THE SYMMETRIC ROTOR 

The term values of the rigid symmetric rotor are given by 

By definition, of the three moments of inertia of symmetric rotor molecules, two are equal and differ from the third. For the equations above, 

In addition, the moment is taken about the axis of inertia which coincides with the principal axis of symmetry (the C axis) of the molecule. 

The spacing of the energy levels depends on the relative magnitudes of and Ig. We shall discuss two particular cases. The first is that for which = Ig Iq- Molecules with this property are called oblate symmetric rotors. Ammonia is such a molecule. The second case is that for which Ic the molecule here is 

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