Abstract
Using a light scattering technique at a fixed temperature, we have investigated viscoelastic behaviour exhibited by the ferroelectric smectic phase (SmC*) of C
8
tolane in a homeotropic orientation. Experiments were performed in backward and forward scattering geometries that allowed us to deduce separately orientational diffusivities k
3
/η and k
+
/η corresponding to the Goldstone mode. The k
3
/η value measured in the SmC* phase is about 100 times higher than in the SmC
A
* phase exhibited by the same liquid crystal compound. The factor 100 may be attributed in great part to the molecular arrangement mode in adjacent smectic layers. However k
+
/η measured in the SmC* phase is in the same order of magnitude as those measured previously in SmC
A
* phases.