Simulated calculation of O atoms displacement modulation model in Bi-2212 superconductors

The modulation structure model by O atoms displacement in the BiO layers has been proposed according to the structure characteristics of Bi high-Tc superconductor.The selected area electron diffraction(SAED) and the convergent beam electron diffraction(CBED) patterns of the modulation model for the Bi-2212 phase have been simulated.The facts that effects of the displacement modulation of the O atoms for the electron diffraction patterns were very obvious indicated that action of the light atoms couldn't be ignored in the electron diffraction.The effects for CBED patterns were more sensitive than SAED,therefore,the advantage may be utilized to ascertain the O atom sites in the modulation structure of the Bi high-Tc superconductors.The patterns simulated for the SAED and the CBED were identical with the experimental results.