00-07E

Energy spectrum and thermodynamics of the proton subsystem of the one-dimensional hydrogen-bonded molecular chain is investigated. The consideration is based on orientational-tunneling model which includes two types of proton transfer according to Grotthuss mechanism. The method of cluster expansions in the theory of Greens' functions is used to calculate the energy spectrum. In the independent subband approximation the spectrum consists of eight energy bands which edges are functions of proton concentration. The investigation of chemical potential behaviour shows that there exist regions where chemical potential is the decreasing function of proton concentration which points out to the possibility of separation. The influence of additional asymmetry field is also investigated.