Behaviour of mesomorphic systems of conformationally rigid and flexible molecules in external orienting fields

(Received 6 August 1990, revised 10 December 1990, accepted 12 December 1990)

Abstract
A comparative analysis of the influence of external orienting quadrupolar symmetry fields on mesophases formed by conformationally rigid and flexible particles with positive susceptibility anisotropy for which weak and strong first order transitions to the isotropic liquid state are, respectively, realized (in the absence of fields) is fulfilled theoretically. Peculiarities allowing to distinguish experimentally mesomorphic systems described adequately by the approximations of rigid and flexible molecules are noted.