Molecular structure of the nematic liquid crystals made by hydrogen bondedin dimers molecules

The dimer molecular structure of 4,n-alkyloxybenzoic acids displaying nemat ic and smectic C liquid crystal phases is investigated. AB INITIO molecular orbital calculations at HF/STO-3G level of theory are applied in order to calculate the molecule of in its closed dimer, open dimer and monomer state s. The molecular geometry parameters (stereoparameters), the thermochemical quantities and molecular polarizability are calculated. The microscopical calculations give a base for development of a mean-field theory where the c onstituent molecule can not be approximated as a rigid rod.