spherical top molecule

Spherical top molecules have no net dipole moment.

Since the spin–rotation constants are accurately known for CH4, the relaxation experiments provide a check on the theory of spin–lattice relaxation for spherical top molecules.

In linear and spherical top molecules, rotational lines are found as simple progressions at both higher and lower frequencies relative to the pure vibration frequency.

The polarizability ellipsoid of spherical top molecules is in fact spherical so those molecules show no rotational Raman spectrum.

He predicted a 'clustering' of energy levels in higher angular momentum states of spherical top molecules, an effect also confirmed by subsequent experiments using ultra-high resolution laser techniques.