ErBa2Cu4O8 has been studied with High Resolution Electron Microscopy to determine whether ErBa2Cu5O9 can be formed locally by the intercalation of Cu and O, in samples heated in the temperature range 100-250°C. Prior to the formation of planar defects, a 2a,b,c superstructure is formed upon heating, occurring only near the surface. The 2a period is present only in the (CuO)2 double layer. Upon heating, several types of planar defects are formed: (1) a set of defects showing an increase in the c lattice parameter of 0.15-0.30 nm; the defects seem to be obtained by insertion of a more or less amorphous layer between the CuO layers of the (CuO)2 double layers; (2) a new group of structures in which extra layers are intercalated between the CuO layers, each layer having a width of 0.28(2) nm. The latter group of structures and the 2a,b,c superstructure can be explained with the presence of CO3 groups in the lattice. Continuous heating above 150°C leads to amorphization, progressing from the surface. No evidence is obtained which would indicate that ErBa2Cu5O9 can be formed under these conditions.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering