Rotational Constants and Molecule Shape:

Explanation:
The rotational constants in the microwave spectrum of a molecule provide important information about its shape and structure. These constants are related to the moments of inertia of the molecule's rotation along its principal axes. Depending on the values of the rotational constants, we can determine the shape of the molecule.

Types of Molecule Shapes:
- Prolate: If a molecule has three distinct rotational constants that are all different, it indicates a prolate shape. In a prolate molecule, the rotational constants along the principal axes are unequal.
- Spherical: A molecule with three equal rotational constants suggests a spherical shape. This means that the moments of inertia along all three principal axes are the same.
- Asymmetric: An asymmetric molecule will have two different rotational constants, indicating that it is not symmetrically shaped.
- Oblate: A molecule with two equal rotational constants and one different constant is considered oblate. In an oblate molecule, two principal moments of inertia are equal, while the third is different.

Conclusion:
By analyzing the rotational constants in the microwave spectrum of a molecule, we can determine its shape and symmetry. This information is crucial for understanding the structural properties and behavior of the molecule in various chemical reactions and interactions.