How do the sizes of molecules change during the transition of a substance from a solid state of aggregation

How do the sizes of molecules change during the transition of a substance from a solid state of aggregation to a gaseous one?

The sizes of the molecules do not change with a change in the state of aggregation of the substance. Only the speed of their movement and the number of degrees of freedom change.

In the crystal lattice of a solid, the molecules are quite rigidly fixed (nevertheless, they can vibrate relative to each other); in the gas phase, the molecules, as a rule, are not connected with each other.