were measured. The lower
value of B found for CB7CB compared with SB 3/5 might be
due to the problems with sample alignment—nearly ideal
homeotropic orientation, which is required for high quality
modulus measurements, was easily obtained for the SB 3/5,
whereas for CB7CB the homeotropic orientation was not
perfect. The value of B in the range of 107 Pa is typical for
smectic phases, while the compressibility of non-modulated
nematic phase is practically zero.