The microscopic theory for BPI and BPII of the blue phase

A statistical theory of the blue phase of chiral liquid crystal is proposed. The form of the interaction potential between molecules is assumed to be the same as that used in the theory for cholesteric phase. Using the cell model of the liquid statistical theory, we deduced the distribution function of single molecule. The free energy of the system obtained has the same form as that of the Ginzberg－Landau phenomenology theory. The order-parameter tensors of BPI and BPII phases we calculated can be compared with the experimental results.