TEM studies of an incommensurate charge ordering modulation in La0.5Ca0.5MnO3

Electron energy-loss spectroscopy in the transmission electron microscope has been used to determine the valence state of manganese in La0.5Ca0.5MnO3 at room temperature and at 93 K. An incommensurate charge ordering modulation in La0.5Ca0.5MnO3 was detected by transmission electron microscopy. A structural model, based on the selected area electron diffraction and high-resolution electron microscopy observation, is proposed for the incommensurate modulation.