Question

Crystalline solids are anisotropic in nature. What does this statement mean?

Answer 1

allcrystalline solids are not anisotropic. Those crystalline solids which are anisotropic, have their atoms arranged and spaced in a different manner in three different planes (X, Y and Z).Therefore, if light is passed through such crystal, it will experience different environments in different directions and hence different refractive indices will be obtained

Answer 2

Some crystalline solids are anisotropicbecause despite showing periodicity they are not exactly the same in all directions. It all depends on the symmetry of the unit cell of the crystal. If its size in the x, y and z direction is the same, it would be isotropic and anisotropic otherwise.