Defects on the (100) planes of La0.8Sr0.2MnO3, which were some 25nm in size, were investigated by means of high-resolution transmission electron microscopy. A systematic comparison was made of experimental <100> and <110> images of the defects, and of calculated images for defect models with vacant La/Sr or Mn atom columns. It was found that the defects consisted of pure La/Sr vacancy defects which were 1 atomic layer thick and had a zero cation occupancy. Due to the high density of defects, the concentration of La/Sr vacancies corresponded to about 1at%La/Sr. Under the imaging conditions which were used, the <110> high-resolution electron microscopic images were sensitive to defects with 75%La/Sr occupancy.

H.Cerva: Journal of Solid State Chemistry, 1995, 114[1], 211-8