ELECTRON CORRELATION AND TWO-DIMENSIONAL LATTICE INSTABILITY
电子关联与二维晶格的不稳定性

Starting from the screened Coulomb electron interaction, the energy band and electron wave function of two-dimensional unstable lattice system are calculated by using the Wannier function. The effect of electron correlation on two-dimensional lattice instability is studied by means of the electron correlation function. Our results show that the electron interaction reduces the two-dimensional lattice dimerization, which is different from the one-dimensional case.