Electron microscopy study of structure of La2-xSrxCuO4 compound with various strontium content

Methods of electron microscopy and X-ray diffraction analysis were used to study atomic-crystal structure of La2-xSrxCuO4 compound with 0.04-0.19 strontium content. It was established that samples of all compositions possessed fine crystalline structure. The mean grain size varies from one to several tens of microns. It is shown that a new phase is present in compounds of all compositions along with superconducting tetragonal phase. A new phase is observed in most of cases in the form of conglomerate of small units with configuration of stretched pattens with cross dimension within the limits of 10-40 nm. Direct resolution of basis planes of tetragonal phase was accomplished. Specific contrast in the form of regularly located particles of 1-2 nm size was revealed. The presence of diffuse scattering effects on electron diffraction patterns was shown