Phase Transitions of SC[.sub.2] Ferroelectrics in [Al.sub.2][O.sub.3]-Based Nanoporous Matrices

Temperature dependences of the linear permittivity [epsilon]' and the third harmonic amplitude [[gamma].sub.3[omega]] of composites prepared by introducing ferroelectrics SC[(N[H.sub.2]).sub.2] into matrices of porous aluminum oxide [Al.sub.2][O.sub.3] with pore sizes 60 and 100 nm are determined. It is found that temperature [T.sub.c] of the ferroelectric phase transition and the temperature [T.sub.i] of the phase transition from incommensurable phase to the paraphrase increase significantly. The transition shifts increase as pore diameters decrease.