DIATOMIC CHAIN WITH MULTI-NEIGHBORS INTERACTION AND LATTICE VIBRATION OF ONE-DIMENSIONAL FERROELECTRIC
多近邻作用双原子链和一维铁电体晶格振动

The lattice vibratoin behavior of the diatomic chain model with multi neighbors was investigated using the real space method. This model is the simple approximation of the ferroelectric. The investigation demonstrates that the long range Coulomb force is really the important cause for the soft mode of phase transition. The new characteristic of the lattice vibration for the impurity was found.