Orientational orders in binary mixtures of hard HGO molecules
studied liquid crystal phases of binary mixtures of non-spherical molecules. The components of the mixtures are two kinds of hard Gaussian overlap (HGO) molecules, one kind of molecules with a small molecular-elongation parameter (small HGO molecules) cannot form stable liquid crystal phase in bulk, and other with a large elongation parameter (large HGO molecules) can form liquid crystal phase easily. In the mixtures, like the large HGO molecules, the small HGO molecules can also form an orientation-ordered phase, which is because that the large HGO molecules can form complex confining surfaces to induce the alignment of the small molecules and generate an isotropic-anisotropic phase transition in the whole binary mixtures. We also study the transition on different mixtures composed of small and large HGO molecules with different elongations and different concentrations of the large molecules. The obtained result implies that small anisotropic molecules might show liquid crystal behavior in confinement.