Cluster Approximations for Order-Disorder-Type Hydrogen-Bonded Ferroelectrics. II. Application to K H 2 P O 4

摘要: A four-particle cluster approximation is worked out for the free energy of ferroelectric K${\mathrm{H}}_{2}$P${\mathrm{O}}_{4}$, taking into account overlap protonic wave functions between two sites in a hydrogen bond as well short-range and long-range forces part proton-lattice interactions. The reduces classical limit to Slater-Takagi-Senko-Uehling treatment order-disorder transition this crystal. It shown that changes Curie temperature, spontaneous polarization, domain-wall mobility on deuteration can be derived from decrease lowering zero-point an anharmonic potential.